Error Propagation in File Handling

Error propagation is a core concept in Rust that allows you to handle errors in a clean and structured way. Instead of having to handle each error manually on every step, you can easily use the ? operator to propagate errors to a higher level so that they can be handled in a single place.

In this challenge, you’ll use io::Error to represent potential issues when working with file I/O. This approach leverages Rust’s standard library for concise and idiomatic error handling.

Your Task

Your task is to implement a function that reads integers from a file, computes their sum, and gracefully propagates any errors using the ? operator.

Implement the function sum_integers_from_file:

Takes the file path as a parameter.
Reads the file line by line, assuming each line contains a single integer or invalid data.
Computes and returns the sum of all integers as a Result<i32, io::Error>.
Handles the following:
- If the file cannot be opened, propagate the io::Error.
- If a line cannot be parsed as an integer, propagate a custom io::Error with a meaningful message.

Requirements

Handle errors cleanly and propagate them using the ? operator.
For invalid lines, create an io::Error with io::ErrorKind::InvalidData.

Hints

If you're stuck, here are some hints to help you solve the challenge:

Click here to reveal hints

Use std::fs::File::open to open a file.
Use io::BufReader::new to read lines from the file.
Convert strings to integers with the str::parse method.
The io::Error::new function can create custom errors.
To create the error type we want for invalid numbers, you can do the following:
```
let error = io::Error::new(io::ErrorKind::InvalidData, "Invalid number");
```
To propagate an error, use the ? operator. e.g.
```
let file = File::open(file_path)?;
```

You can transform an error type to another error type by using the map_err method. e.g.

let num = num_str.parse::<i32>().map_err(|_| io::Error::new(io::ErrorKind::InvalidData, "Invalid number"))?;

Editor not available on Mobile!

In order to solve the challenge, please visit this page on a desktop computer.

Solutions

Seth Wood

seth-wood

6 days ago

5.84ms

96.16kb

use std::fs;
use std::io;
use std::io::BufRead;
use std::io::BufReader;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    let file = fs::File::open(file_path)?;
    let reader = BufReader::new(file);
    reader
        .lines()
        .map(|line| {
            line?
                .parse::<i32>()
                .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))
        })
        .try_fold(0, |acc, num| Ok(acc + num?))
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Kanak Shilledar

kanakshilledar

7 days ago

6.56ms

88.06kb

use std::fs::File;
use std::io::read_to_string;
use std::io::Error;
use std::io::ErrorKind;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path).map_err(|_|Error::new(ErrorKind::InvalidInput, "Failed to open a file!"))?;
    let whole = read_to_string(file).map_err(|_| Error::new(ErrorKind::InvalidData, "Invalid file content"))?;
    let lines : Vec<String> = whole.lines().map(String::from).collect();
    
    let mut result = 0;
    for line in lines.iter() {
        let num = line.parse::<i32>().map_err(|_| Error::new(ErrorKind::InvalidData, "Invalid number"))?;
        result += num;
    }
    Ok(result)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Nicolai

Posmac

8 days ago

6.94ms

88.06kb

use std::fs::File;
use std::io::read_to_string;
use std::io::Error;
use std::io::ErrorKind;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path).map_err(|_|Error::new(ErrorKind::InvalidInput, "Failed to open a file!"))?;
    let whole = read_to_string(file).map_err(|_| Error::new(ErrorKind::InvalidData, "Invalid file content"))?;
    let lines : Vec<String> = whole.lines().map(String::from).collect();
    
    let mut result = 0;
    for line in lines.iter() {
        let num = line.parse::<i32>().map_err(|_| Error::new(ErrorKind::InvalidData, "Invalid number"))?;
        result += num;
    }
    Ok(result)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Thomastienn

11 days ago

5.02ms

96.22kb

use std::fs::File;
use std::io::{BufRead, BufReader, Error, ErrorKind};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    let mut sum = 0;
    for line in reader.lines() {
        let error = Error::new(ErrorKind::InvalidData, "Invalid number");
        match line.unwrap().parse::<i32>() {
            Ok(num) => sum += num,
            Err(_) => return Err(error),
        }
    }
    return Ok(sum);
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Health-Care-Movie

12 days ago

5.85ms

96.16kb

use std::io::{BufReader, BufRead, Error, ErrorKind};
use std::fs::File;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let buf_reader = BufReader::new(file);
    let mut sum:i32 = 0;
    for line in buf_reader.lines() {
        let parse_res = line.unwrap().parse::<i32>();
        match parse_res {
            Err(_) => return Err(Error::new(ErrorKind::InvalidData, "oops")),
            Ok(val) => sum += val,
        }
    }
    return Ok(sum);
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Elizabeth Doughty

Thymelizabeth

12 days ago

6.37ms

96.16kb

use std::io::{BufReader, BufRead, Error, ErrorKind};
use std::fs::File;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    BufReader::new(File::open(file_path)?).lines().try_fold(0, |acc, line| {
        Ok(line?.parse::<i32>().map_err(|_| Error::new(ErrorKind::InvalidData, "Not i32 on each line"))? + acc)
    })
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Splatrac

splatrac

13 days ago

5.53ms

96.16kb

use std::fs::File;
use std::io::{BufRead, BufReader, Error as IoError, ErrorKind};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, IoError> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    let mut sum = 0;
    for line in reader.lines() {
        let line = line?;
        let num = line.parse::<i32>().map_err(|_| IoError::new(ErrorKind::InvalidData, "Invalid number"))?;
        sum += num;
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Nguyen Vo Hoang Son

sonmessia

13 days ago

7.49ms

87.69kb

use std::fs;
use std::io;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    match fs::read_to_string(&file_path) {
        Ok(content) => {
            let mut sum = 0;
            for line in content.lines() {
                match line.trim().parse::<i32>() {
                    Ok(num) => sum += num,
                    Err(_) => return Err(io::Error::new(io::ErrorKind::InvalidData, "Invalid data")),
                }
            }
            return Ok(sum);
        },
        Err(e) => return Err(e),
    };
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Trịnh Chấn Duy

Duyyy123

15 days ago

6.60ms

96.16kb

use std::fs::{remove_file, write, File};
use std::io::{self, BufRead, BufReader};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    reader
        .lines()
        .map(|l| {
            l.unwrap()
                .parse::<i32>()
                .map_err(|_| io::Error::new(io::ErrorKind::InvalidData, "oh no"))
        })
        .sum()
}
// Example usage
pub fn main() {
    let file_path = "test_invalid.txt";
    write(file_path, "10\nabc\n30\n").unwrap();
    let result = sum_integers_from_file(file_path);
    match result {
        Err(ref e) => {
            print!("{}", e.to_string());
        }
        _ => {}
    };
    assert!(matches!(
        result,
        Err(ref e) if e.kind() == io::ErrorKind::InvalidData
    ));
    remove_file(file_path).unwrap();
}

Liyqq

16 days ago

6.61ms

96.16kb

use std::fs::File;
use std::io;
use std::io::BufRead;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let reader = io::BufReader::new(file);
    reader.lines().map(|ln| {
        ln?.parse::<i32>()
           .map_err(|_| io::Error::new(io::ErrorKind::InvalidData, "Invalid number"))
    }).sum()
}
// Example usage
pub fn main() {
    let file_path = "./src/numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {sum}"),
        Err(e) => eprintln!("Error: {e}"),
    }
}

agamaontherock

17 days ago

5.31ms

96.16kb

use std::fs::File;
use std::io::BufReader;
use std::io::BufRead;
use std::io; 
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let buf_reader = BufReader::new(file);
    let mut sum:i32 = 0;
    for line in buf_reader.lines() {
        let parse_res = line.unwrap().parse::<i32>();
        match parse_res {
            Err(_) => return Err(io::Error::new(io::ErrorKind::InvalidData, "oops")),
            Ok(val) => sum += val,
        }
    }
    return Ok(sum);
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Felix Kiprotich

penscola

20 days ago

6.11ms

96.16kb

use std::fs::File;
use std::io::{self, BufRead, BufReader, Error, ErrorKind};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    let mut sum: i32 = 0;
    for lines in reader.lines() {
       
       match lines?.parse::<i32>() {
        Ok(num) => {
            sum += num;
        }
        Err(_) => {
            let error = Error::new(ErrorKind::InvalidData, "Invalid number");
            return Err(error);
        }
        }
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Neel Knight

NeelKnight

23 days ago

4.56ms

96.16kb

use std::fs::File;
use std::io::{self, BufRead, BufReader, Error, ErrorKind};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    let mut sum: i32 = 0;
    for lines in reader.lines() {
       
       match lines?.parse::<i32>() {
        Ok(num) => {
            sum += num;
        }
        Err(_) => {
            let error = Error::new(ErrorKind::InvalidData, "Invalid number");
            return Err(error);
        }
        }
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Maintain

duonghb53

25 days ago

7.48ms

96.16kb

use std::fs::File;
use std::io::{self, BufReader, Error, ErrorKind, BufRead};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let f = File::open(file_path)?;
    let mut sum: i32 = 0;
    let reader = BufReader::new(f);
    for line in reader.lines() {
        let num = line?.parse::<i32>().map_err(|_| Error::new(ErrorKind::InvalidData, "Invalid number"))?;
        sum += num;
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Nguyen Vo Hoang Son

sonmessia

a month ago

7.91ms

96.16kb

use std::io::{self, BufReader, Error, ErrorKind, BufRead};
use std::fs::File;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    let mut result = 0;
    for line in reader.lines() {
        result += line?.parse::<i32>().map_err(|_| Error::new(ErrorKind::InvalidData, "invalid Data"))?;
    }
    Ok(result)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Nathan GAUD

Natchica

a month ago

5.48ms

96.16kb

use std::io::{self, BufReader, BufRead};
use std::fs::File;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path.to_string())?;
    let reader = BufReader::new(file);
    let mut sum: i32 = 0;
    for line in reader.lines() {
        match line?.parse::<i32>() {
            Ok(num) => sum += num,
            Err(e) => return Err(io::Error::new(io::ErrorKind::InvalidData, e)),
        }
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Paolo Cancedda

Pac72

a month ago

4.93ms

96.16kb

use std::{io, io::BufReader, io::prelude::*};
use std::fs::File;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    let f = File::open(file_path)?;
    let reader = BufReader::new(f);
    reader.lines()
        .try_fold(0_i32, |acc, line| {
            let line = line?;
            line.parse::<i32>()
                .map(|value| acc + value)
                .map_err(|_| io::Error::new(io::ErrorKind::InvalidData, format!("Invalid i32 value \"{line}\"")) )
        })
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Paolo Cancedda

Pac72

a month ago

6.37ms

96.16kb

use std::io::prelude::*;
use std::io::BufReader;
use std::fs::File;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, std::io::Error> {
    let f = File::open(file_path)?;
    let reader = BufReader::new(f);
 
    reader.lines()
        .try_fold(0_i32, |acc, line| {
            let line = line?;
            let value = line.parse::<i32>();
            match value {
                Ok(value) => Ok(acc + value),
                Err(_) => Err(std::io::Error::new(std::io::ErrorKind::InvalidData, format!("Invalid i32 value \"{line}\"")))
            }                                                                                                                                                                              })
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
 
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

mishbah

a month ago

4.90ms

96.16kb

use std::{
    fs::File,
    io::{self, BufRead, BufReader},
};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    let file = File::open(file_path)?;
    let lines = BufReader::new(file).lines();
    let mut result = 0;
    for line in lines {
        result += line?
            .parse::<i32>()
            .map_err(|_| io::Error::new(io::ErrorKind::InvalidData, "Invalid number"))?;
    }
    Ok(result)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

asdfman

a month ago

5.21ms

96.16kb

use std::io::BufRead;
use std::io;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = std::fs::File::open(file_path)?;
    let reader = std::io::BufReader::new(file);
    let mut sum = 0;
    for line in reader.lines() {
        match line.unwrap().parse::<i32>() {
            Ok(i) => sum += i,
            Err(..) => return Err(io::Error::new(io::ErrorKind::InvalidData, "Invalid number"))
        }
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

RASHMOR

RASHMOR1

a month ago

6.28ms

96.16kb

use std::fs::File;
use std::io::{self, BufRead, BufReader, Error, ErrorKind}; // Import everything needed
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    // Read lines and sum valid integers
    let mut sum = 0;
    for line in reader.lines() {
        let line = line?; // Propagate file read errors
        match line.trim().parse::<i32>() {
            Ok(num) => sum += num,
            Err(_) => return Err(io::Error::new(io::ErrorKind::InvalidData, "Invalid number in file")),
        }
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

romaingz

a month ago

6.14ms

96.16kb

use std::fs;
use std::io::{self, prelude::*, ErrorKind};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let fp = fs::File::open(file_path)?;
    let reader = io::BufReader::new(fp);
    let mut sum: i32 = 0;
    for line in reader.lines() {
        if line.is_err() {
            return Err(io::Error::new(ErrorKind::InvalidData, "toto"));
        }
        let parse_result = line.unwrap().parse::<i32>();
        if parse_result.is_ok() {
            sum += parse_result.unwrap();
        } else {
            return Err(io::Error::new(ErrorKind::InvalidData, "toto"));
        }
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Jakub Wiśniewski

wisniewskij

a month ago

5.49ms

96.16kb

use std::fs::File;
use std::io::{self, BufRead, BufReader};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, std::io::Error> {
    let file = File::open(file_path)?;
    let mut bufReader = BufReader::new(file);
    let mut sum: i32 = 0;
    for line in bufReader.lines() {
        let line = line?;
        let number = line.trim().parse::<i32>().map_err(|e| {
            io::Error::new(io::ErrorKind::InvalidData, format!("invalid data format: {}", e))
        })?;
        sum += number;
    }
    return Result::Ok(sum);
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

vijayabhaskar badireddi

ptcte

a month ago

4.21ms

96.16kb

use std::fs::File;
use std::io::{self, BufRead, BufReader};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    let mut sum = 0;
    for line in reader.lines() {
        let line = line?;
        let number = line.trim().parse::<i32>().map_err(|e| {
            io::Error::new(
                io::ErrorKind::InvalidData,
                format!("invalid data format: {}", e),
            )
        })?;
        sum += number;
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Jason

Jason-fy-wang

a month ago

4.80ms

96.16kb


use std::fs::File;
use std::io::{self, BufRead,BufReader};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    let mut sum = 0;
    for line in reader.lines() {
        let line = line?;
        let number = line.trim().parse::<i32>().map_err(|e| {
            io::Error::new(io::ErrorKind::InvalidData, format!("invalid data format: {}", e))
        })?;
        sum += number;
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Jason

Jason-fy-wang

a month ago

6.18ms

96.16kb


use std::fs::File;
use std::io::{self, BufRead,BufReader};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    let mut sum = 0;
    for line in reader.lines() {
        let line = line?;
        let number = line.trim().parse::<i32>().map_err(|e| {
            io::Error::new(io::ErrorKind::InvalidData, format!("invalid data format: {}", e))
        })?;
        sum += number;
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Nhat Vu

NhatTinyVu

a month ago

6.10ms

96.16kb

use std::fs::File;
use std::io::{self, BufRead, BufReader};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    let mut sum = 0;
    for line in reader.lines() {
        let line = line?;
        let number: i32 = line.trim().parse().map_err(|_| {
            io::Error::new(
                io::ErrorKind::InvalidData,
                format!("Invalid integer in file: {}", line),
            )
        })?;
        sum += number;
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Levio-z

a month ago

5.40ms

96.16kb

use std::io::ErrorKind;
use std::io::BufReader;
use std::fs::File;
use std::io;
use std::io::prelude::*;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let f1 = File::open(file_path)?;
    let reader = BufReader::new(f1);
    let mut count = 0;
    for (index,line) in reader.lines().enumerate(){
        let num = line?
            .parse::<i32>()
            .map_err(|_| {
                io::Error::new(ErrorKind::InvalidData, "Invalid number")
            })?;
        count +=num;
    }
    Ok(count)
  
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

shibu-t

a month ago

4.81ms

96.16kb

use std::fs::File;
use std::io::BufReader;
use std::io::{self, BufRead};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    let mut sum = 0;
    for line in reader.lines() {
        sum += line?.parse::<i32>().map_err(|_| io::Error::new(io::ErrorKind::InvalidData, "Invalid number"))?;
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Levio-z

a month ago

5.68ms

96.16kb

use std::io::ErrorKind;
use std::io::BufReader;
use std::fs::File;
use std::io;
use std::io::prelude::*;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
   let f1 = File::open(file_path)?;
    let reader = BufReader::new(f1);
    let mut count = 0;
    for line in reader.lines(){
        let num = line?
            .parse::<i32>()
            .map_err(|_| {
                io::Error::new(ErrorKind::InvalidData, "Invalid number")
            })?;
        count +=num;
    }
    Ok(count)
  
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

roboquaternion

a month ago

7.07ms

96.16kb

use std::io::{Error, ErrorKind, BufReader, BufRead};
use std::fs::File;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let buf_reader = BufReader::new(file);
    let mut sum = 0;
    for line_result in buf_reader.lines() {
        let line = line_result?;
        let num: i32 = line
            .parse()
            .map_err(|_| Error::new(ErrorKind::InvalidData, "Invalid number"))?;
        sum += num;
    }
    Ok(sum)   
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Douglas Campbell

CampbellD84

a month ago

4.61ms

96.17kb

use std::fs::File;
use std::io::{self, BufReader};
use std::io::BufRead;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let buffer_reader = BufReader::new(file);
    let mut result = Vec::new();
    for line in buffer_reader.lines() {
        let num = line?.parse::<i32>()
            .map_err(|_|
            io::Error::new(io::ErrorKind::InvalidData, "Invalid number"))?;
        
            result.push(num);
        }
    let sum = result.iter().sum();
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Marcel Schiffel

mschiffel

a month ago

6.62ms

95.58kb

use std::{
    fs::File,
    io::{self, BufRead, BufReader, Error},
};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, Error> {
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    let mut sum = 0;
    for line in reader.lines() {
        let line = line?;
        let number = line.parse::<i32>();
        match number {
            Ok(number) => sum += number,
            Err(error) => return Err(io::Error::new(io::ErrorKind::InvalidData, error)),
        }
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

ON-MX

a month ago

5.12ms

96.16kb

use std::fs::File;
use std::io::{Error,ErrorKind,BufRead,BufReader};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    let mut result = 0;
    for line in reader.lines() {
        result += line?.parse::<i32>().map_err(|_| Error::new(ErrorKind::InvalidData, "invalid Data"))?;
    }
    Ok(result)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Assylbek Razakhbergenov

asylbek27

a month ago

4.83ms

96.16kb

use std::fs::File;
use std::io;
use std::io::BufRead;
use std::io::BufReader;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    let mut result = 0;
    for line in reader.lines() {
        let num = line?.parse::<i32>().map_err(|_| io::Error::new(io::ErrorKind::InvalidData, "invalid Data"))?;
        result += num;
    }
    Ok(result)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

VLund

VladikPopik

a month ago

5.26ms

96.16kb

use std::{
    fs::File,
    io::{self, BufRead, BufReader},
};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let lines = BufReader::new(file).lines();
    let mut sum = 0;
    for line in lines {
        let num = line?
            .parse::<i32>()
            .map_err(|_| io::Error::new(io::ErrorKind::InvalidData, "Invalid number"))?;
        sum += num;
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Kondorok

a month ago

20.89ms

95.60kb

use io::ErrorKind;
use std::fs::File;
use std::io;
use std::io::BufRead;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let reader = io::BufReader::new(file);
    let mut sum: i32 = 0;
    for line_result in reader.lines() {
        let line = line_result?;
        let num: i32 = line
            .trim()
            .parse()
            .map_err(|_| io::Error::new(io::ErrorKind::InvalidData, ""))?;
        sum += num;
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Jason

chenjie1219

2 months ago

7.53ms

96.16kb

use std::{
    fs::File,
    io::{self, BufRead, BufReader},
};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let lines = BufReader::new(file).lines();
    let mut sum = 0;
    for line in lines {
        let num = line?
            .parse::<i32>()
            .map_err(|_| io::Error::new(io::ErrorKind::InvalidData, "Invalid number"))?;
        sum += num;
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Yixian Du

duyixian1234

2 months ago

5.73ms

87.69kb

use std::io;
use std::fs;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    match fs::read_to_string(&file_path) { // Attempt to read the file contents
        Ok(content) => {
            let mut sum = 0;
            for line in content.lines() {
                match line.trim().parse::<i32>() {
                    Ok(num) => sum += num,
                    Err(_) => return Err(io::Error::new(io::ErrorKind::InvalidData, "Invalid data")),
                }
            }
            return Ok(sum);
        }
        Err(e) => return Err(e)
    };
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

VerweyFr

2 months ago

5.33ms

87.69kb

use std::io;
use std::fs;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    match fs::read_to_string(&file_path) { // Attempt to read the file contents
        Ok(content) => {
            let mut sum = 0;
            for line in content.lines() {
                match line.trim().parse::<i32>() {
                    Ok(num) => sum += num,
                    Err(_) => return Err(io::Error::new(io::ErrorKind::InvalidData, "Invalid data")),
                }
            }
            return Ok(sum);
        }
        Err(e) => return Err(e)
    };
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

rolan

rolan36

2 months ago

5.22ms

96.17kb

use std::io::{self, BufReader};
use std::fs::File;
use std::io::BufRead;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let buffer_reader = BufReader::new(file);
    let mut res = Vec::new();
  
    for line in buffer_reader.lines(){
        let num = line?
            .parse::<i32>()
            .map_err(|_|
                io::Error::new(io::ErrorKind::InvalidData, "Invalid number"))?;
        
        res.push(num);
    }
    let sum = res.iter().sum();
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

gsspdev

2 months ago

4.86ms

96.16kb

use std::fs::File;
use std::io::{BufRead, BufReader, Error, ErrorKind};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, Error> {
    let file = File::open(file_path)?;
    let buffered_reader = BufReader::new(file);
    let mut sum = 0;
    
    for line in buffered_reader.lines() {
        if let Ok(num) = line?.parse::<i32>() {
            sum += num
        } else {
            return Err(Error::new(ErrorKind::InvalidData, "Invalid number"));
        }
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

panda wiz

pandamrx

2 months ago

4.55ms

96.17kb

use std::io::{self, BufRead};
use std::fs::File;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let mut result: Vec<i32> = Vec::new();
    for line in io::BufReader::new(file).lines() {
        let num_str = String::from(line?);
        let num = num_str
            .parse::<i32>()
            .map_err(|_| io::Error::new(io::ErrorKind::InvalidData, "Invalid number"))?;
        result.push(num);
    }
    let sum: i32 = result.iter().sum();
    
    return Ok(sum);
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Aurimas Kuniutis

auriku

2 months ago

5.23ms

96.16kb

use std::fs::File;
use std::io::{BufRead, BufReader, Error, ErrorKind};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, Error> {
    let file = File::open(file_path)?;
    let buffered_reader = BufReader::new(file);
    let mut sum = 0;
    for line in buffered_reader.lines() {
        let num = line?
            .parse::<i32>()
            .map_err(|_| Error::new(ErrorKind::InvalidData, "Invalid number"))?;
        sum += num;
        // if let Ok(num) = line?.parse::<i32>() {
        //     sum += num
        // } else {
        //     return Err(Error::new(ErrorKind::InvalidData, "Invalid number"));
        // }
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Aurimas Kuniutis

auriku

2 months ago

4.44ms

96.16kb

use std::fs::File;
use std::io::{BufRead, BufReader, Error, ErrorKind};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, Error> {
    let file = File::open(file_path)?;
    let buffered_reader = BufReader::new(file);
    let mut sum = 0;
    for line in buffered_reader.lines() {
        // let num = line?
        //     .parse::<i32>()
        //     .map_err(|_| Error::new(ErrorKind::InvalidData, "Invalid number"))?;
        // sum += num;
        if let Ok(num) = line?.parse::<i32>() {
            sum += num
        } else {
            return Err(Error::new(ErrorKind::InvalidData, "Invalid number"));
        }
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

lugtester

2 months ago

8.64ms

96.16kb

use std::fs::File;
use std::io::{self, BufReader, BufRead};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    let mut sum = 0;
    for line in reader.lines() {
        let result = line?.parse::<i32>().map_err(|_| io::Error::new(io::ErrorKind::InvalidData, "Invalid number"))?;
        sum += result;
    }
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

Dhananjay Pandit

djpandit007

2 months ago

5.96ms

96.16kb

use std::fs::File;
use std::io::{self, prelude::*, BufReader};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let reader = BufReader::new(file);
    let mut sum: i32 = 0;
    for line in reader.lines() {
        let num = line?.
            parse::<i32>().
            map_err(|_| io::Error::new(io::ErrorKind::InvalidData, "Invalid number"))?;
        sum += num;
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

linz

hnlinzhi19

2 months ago

19.37ms

95.60kb

use std::fs::File;
use std::io::{self, BufRead, BufReader};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let content = BufReader::new(file);
    let mut sum: i32 = 0;
    for line in content.lines() {
        let line = line?;
        let col = line
            .parse::<i32>()
            .map_err(|_| io::Error::new(io::ErrorKind::InvalidData, ""));
        sum += col?;
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

linz

hnlinzhi19

2 months ago

6.95ms

95.60kb

use std::fs::File;
use std::io::{self, BufRead, BufReader};
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let file = File::open(file_path)?;
    let content = BufReader::new(file);
    let mut sum: i32 = 0;
    for line in content.lines() {
        let line = line?;
        let col = line
            .parse::<i32>()
            .map_err(|_| io::Error::new(io::ErrorKind::InvalidData, ""));
        sum += col?;
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}

JeromeCheze

2 months ago

5.81ms

95.55kb

use std::io::{self,BufReader};
use std::io::prelude::*;
use std::fs::File;
pub fn sum_integers_from_file(file_path: &str) -> Result<i32, io::Error> {
    // TODO: Implement this function
    // Hint: Use `File::open`, `BufReader::new`, and `.lines()` to process the file.
    // Use `?` to propagate errors and `io::Error::new` for custom errors.
    let mut sum: i32 = 0;
    let f = File::open(file_path)?;
    let f = BufReader::new(f);
    for line in f.lines() {
        let line = line?;
        match line.parse::<i32>() {
            Ok(v) => sum += v,
            Err(_) => return Err(io::Error::from(io::ErrorKind::InvalidData))
        }
    }
    Ok(sum)
}
// Example usage
pub fn main() {
    let file_path = "numbers.txt";
    match sum_integers_from_file(file_path) {
        Ok(sum) => println!("The sum is: {}", sum),
        Err(e) => eprintln!("Error: {}", e),
    }
}