Is Prime

Checking Prime Numbers

Prime numbers are natural numbers greater than 1 that have no positive divisors other than 1 and themselves. Determining whether a number is prime is a fundamental problem in number theory and has applications in various fields, including cryptography and computer science.

In this challenge, you will implement a function to check if a given number is prime. You will use logical operators and conditional statements to handle the multiple conditions required to identify a prime number efficiently.

Your task

Your task is to complete the function is_prime(n: u32) -> bool that takes an unsigned integer n and returns a boolean value indicating whether n is a prime number.

Requirements

The function should return true if n is a prime number and false otherwise.
A prime number is a natural number greater than 1 that is not divisible by any number other than 1 and itself.
Use logical operators and conditional statements to check the conditions for a prime number.
Optimize the function to minimize unnecessary checks.

Example

let result = is_prime(5);
assert_eq!(result, true);
 
let result = is_prime(4);
assert_eq!(result, false);

Hints

Any number less than 2 is not prime.
The number 2 is the only even prime number.
For any other even number greater than 2, return false.
Check divisibility starting from 3 up to the square root of the number.

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Solutions

Ramon Silva

rsilva1

an hour ago

3.15ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2 {
        return false;
    }
    if n == 2 || n == 3 {
        return true;
    }
    if n % 2 == 0 {
        return false;
    }
    let mut i = 3;
    loop {
        if n % i == 0 {
            return false;
        }
        if i * i > n {
            return true;
        }
        i += 2;
    };
}

emiludenz

12 hours ago

3.46ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n <= 1 {
        return false
    }
    if n == 2 {
        return true
    }
    for i in 2..n {
        if n % i == 0 {
            return false
        }
    }
    true
}

azmahflameheart

2 days ago

3.16ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 { return false; }
    if n % 2 == 0 { return n == 2; }
    let mut d = 3;
    while d * d <= n {
        if n % d == 0 { return false; }
        d += 2;
    }
    true
}

Marouan Boulahtouf

MBoulahtouf

2 days ago

2.82ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    match n {
        0 | 1 => false,
        2 => true,
        n if n % 2 == 0 => false,
        _ => {
            let sqrt_n = (n as f64).sqrt() as u32;
            !(2..=sqrt_n).any(|i| n % i == 0)
        }
    }
}

Holly Gent

PointlessParrot

4 days ago

3.29ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2 { return false; }
    if n == 2 { return true; }
    if n % 2 == 0 { return false; }
    let mut i = 2;
    while i * i <= n {
        i += 1;
    }
    !(3..=i).any(|x| n % x == 0)
}

Egu0

egu0

6 days ago

2.96ms

81.43kb

// Hints:
//    Any number less than 2 is not prime.
//    The number 2 is the only even prime number.
//    For any other even number greater than 2, return false.
//    Check divisibility starting from 3 up to the square root of the number.
pub fn is_prime(n: u32) -> bool {
    let end = (n as f64).sqrt() as u32;
    if n == 1 {
        return false;
    }
    if n == 2 {
        return true;
    }
    if n % 2 == 0 {
        return false;
    }
    for i in (3..=end).step_by(2) {
        if n % i == 0 {
            return false;
        }
    }
    true
}

makinpaper

8 days ago

3.14ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    match n {
        0 | 1 => false,
        2 => true,
        n if n % 2 == 0 => false,
        _ => (3..=(n as f64).sqrt() as u32)
            .step_by(2)
            .all(|d| n % d != 0),
    }
}

Asrul Firdaus

AsrulF

9 days ago

3.02ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false;
    }
    if n == 2 {
        return true;
    }
    if n % 2 == 0 {
        return false;
    }
    let mut i = 3;
    while i * i <= n {
        if n % i == 0 {
            return false;
        }
        i += 2; // cukup cek bilangan ganjil saja
    }
    true
}

Anton

majesty-dump

9 days ago

2.99ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2{
        return false;
    }
    if n == 2 {
        return true;
    }
    let checking_border = (n as f64).sqrt() as u32; 
    for i in 2..=checking_border {
        if n % i == 0 {
            return false;
        }
    }
    return true;
}

Anton

majesty-dump

9 days ago

2.78ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2{
        return false;
    }
    if n == 2 {
        return true;
    }
    let checking_border = (n as f64).sqrt() as u32; 
    for i in 2..=checking_border {
        if n % i == 0 {
            return false;
        }
    }
    return true;
}

miel-codeai

11 days ago

3.15ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n <= 1 {
        false
    } else {
        let n_sqrt = (n as f32).sqrt().trunc() as u32;
        for i in 2..=n_sqrt {
            if n % i == 0 {
                return false;
            }
        }
        true
    }
}

Anton

majesty-dump

13 days ago

3.13ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2 {
        return false;
    } 
    
    let border : u32 = (n as f64).sqrt().trunc() as u32;
    
    for i in 2..=border {
        if n % i == 0 {
            return false;
        }
    }
    return true;
}

Kishan

wdcs-kishansudani

15 days ago

2.62ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    match n {
        n if n < 2 => false,
        n if n == 2 => true,
        n if n % 2 == 0 => false,
        n => {
            for i in 2..n {
                if n % i == 0 {
                    return false;
                }
            }
            true
        }
    }
}

<YoungAncient/>

youngancient

15 days ago

3.33ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false;
    }
    if n == 2 {
        return true;
    }
    if n % 2 == 0{
        return false;
    }
    let sqrt_floor = (n as f64).sqrt().floor() as u32;
    
    for i in 3..=sqrt_floor{
        if (n % i == 0) && (n != i){
            return false;
        }
    }
    return true;
}

Retroz

Fungichi

16 days ago

3.25ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    match n {
        n if n < 2 => false,
        n if n == 2 => true,
        n if n % 2 == 0 => false,
        n if can(n) => true,
        _ => false,
    }
}
pub fn can(n: u32) -> bool {
    let end = (n as f32).sqrt();
    for i in 3..=end as i32 {
        if n % i as u32  == 0 {
            return false;
        }
    }
    true
}

Retroz

Fungichi

16 days ago

3.73ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    match n {
        n if n < 2 => false,
        n if n == 2 => true,
        n if n % 2 == 0 => false,
        n if can(n) => true,
        _ => false,
    }
}
pub fn can(n: u32) -> bool {
    let end = (n as f32).sqrt();
    for i in 3..=end as i32 {
        if n % i as u32  == 0 {
            return false;
        }
    }
    true
}

Retroz

Fungichi

16 days ago

3.27ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    match n {
        n if n < 2 => false,
        n if n == 2 => true,
        n if n % 2 == 0 => false,
        n if can(n) => true,
        _ => false,
    }
}
pub fn can(n: u32) -> bool {
    let end = (n as f32).sqrt();
    for i in 3..=end as i32 {
        if n % i as u32  == 0 {
            return false;
        }
    }
    true
}

Sheren Yogesh Narayanan

Nsy97

18 days ago

3.73ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if ( n == 2) || n == 3 || n == 5 || n == 7 {
        true
    }
    else if (n % 3 == 0) || (n % 2 == 0) || (n % 5 == 0) || (n % 7 == 0) || (n < 2) {
        false
    }
    else {
        true
    }
}

FredoPo

18 days ago

3.00ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false;
    }
    let n_f32 = n as f32;
    let sqrt = n_f32.sqrt() as i32;
    for i in 2..=sqrt as u32 {
        if n % i == 0 && n != i {
            return false;
        }
    }
    true
}

Chawin Chaisongkram

chawinkn

19 days ago

3.35ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n <= 1 {
        return false;
    }
    let mut i: u32 = 2;
    while i*i <= n {
        if n%i == 0 {
            return false;
        }
        i += 1;
    }
    return true;
}

Dharm Singh

dharmvr1

19 days ago

2.89ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n <= 1 {
        return false;
    }
    for i in 2..=((n as f64).sqrt() as u32) {
        if n % i == 0 {
            return false;
        }
    }
    true
}

Pavel Potapkin

potapkin-pavel

20 days ago

3.38ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    match n {
        1 => false,
        n => !(2..n).any(|x| n % x == 0)
    }
}

noname

random1106

21 days ago

2.89ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n == 1 {
        return false;
    } else {
        for i in 2..n {
            if n % i == 0 {
                return false;    
            }
        } 
    }
    return true;
}

shahab-tplus

22 days ago

3.06ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false
    } else if n == 2 {
        return true
    } else if n % 2 == 0 {
        return false
    }
    let s = (n as f32).sqrt().floor() as u32;
    for i in 3..=s {
        if n % i == 0 {
            return false
        }
    }
    true
}

Vincent SAMY

vsamy

a month ago

4.14ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n == 2 {
        return true;
    }
    if n == 1 || n % 2 == 0 {
        return false;
    }
    !(3..(n / 2)).step_by(2).any(|i| n % i == 0)
}

Ari Karim

arikarim

a month ago

3.70ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2 {
        return false;
    }
    for i in 2..=((n as f64).sqrt() as u32) {
        if n % i == 0 {
            return false;
        }
    }
    true
}

Tim

timvyy

a month ago

3.31ms

81.43kb


pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n <= 1 {
        false
    } else {
        for i in 2..n {
            if n % i == 0 {
                return false;
            }
        }
        true
    }
}

Rubén Moreno aguado

rmaguado

a month ago

3.96ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n == 1 {
        return false;
    }
    let n_f = (n as f32).sqrt() as u32;
    for i in 2..=n_f {
        if n % i == 0 {
            return false;
        }
    }
    return true;
}

Rubén Moreno aguado

rmaguado

a month ago

12.64ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n == 1 {
        return false;
    }
    let n_f = (n as f32).sqrt() as u32;
    for i in 2..=n_f {
        if n % i == 0 {
            return false;
        }
    }
    return true;
}

jh4vision

a month ago

3.10ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    match n{
        (0..=1) => false,
        2   => true,
        n => {
            if n%2 ==0 {
                return false;
            } 
            for m in (3..= (n as f32).sqrt() as u32).step_by(2) {
                if n%m ==0 {
                    return false;
                }
            }
            true
        }
    }
}

Christophe Mohimont

mohic

a month ago

4.46ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2 {
        return false;
    }
    if n == 2 {
        return true;
    }
    if n % 2 == 0 {
        return false;
    }
    let mut i = 3;
    while i * i <= n {
        if n % i == 0 {
            return false;
        }
        i += 2;
    }
    true
}

Prakash Mardi

Mardiprk

2 months ago

3.24ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2 {
        return false;
    }
    for i in 2..n{
        if n % i == 0{
            return false;
        }
    }
    true
}

msned

2 months ago

3.47ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    match n{
        0|1 => false,
        _ => {for i in 2..=n/2{
                if n % i == 0{
                    return false;
                }
            }
            return true;}
            }
}

Splatrac

splatrac

2 months ago

2.96ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false;
    }
    for i in 2..n {
        if n % i == 0 {
            return false;
        }
    }
    true
}

Omar

OmniKobra

2 months ago

3.26ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    match n {
        0 | 1 => false,
        2 => true,
        n if n % 2 == 0 => false,
        _ => (3..=(n as f32).sqrt() as u32).all(|d| n % d != 0)
    }
}

TheJanzap

2 months ago

2.92ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    match n {
        0 | 1 => false,
        2 => true,
        n if n % 2 == 0 => false,
        _ => (3..=(n as f32).sqrt() as u32).all(|d| n % d != 0)
    }
}

ghoti225

2 months ago

3.38ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // This function efficiently checks if a number is prime by first handling small cases and then checking 
    // divisibility by numbers from 5 upwards, skipping even numbers to reduce unnecessary checks.
    match n {
        0 => false,
        1 => false,
        2 => true,
        3 => true,
        _ => {
            
            if n % 2 == 0 || n % 3 == 0 {
                return false;
            }
            let mut ii = 5;
            while ii * ii <= n {
                if n % ii == 0 || n % (ii + 2) == 0 {
                    return false;
            }
            ii += 6;
    }
    true
        }
    }
}

Miguel Ángel Allende

maallende

2 months ago

3.01ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n<2{
        return false;
    }
    if n == 2{
        return true;
    }
    if n % 2==0{
        return false;
    }
    let mut prime:bool = true;
    let mut index = 3;
    while prime && index<(n/2){
        prime = n % index != 0;
        index +=1;
    }
    prime
}

Atty0010

2 months ago

3.24ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false;
    }
    if n == 2 || n == 3 {
        return true;
    }
    if n % 2 == 0 || n % 3 == 0 {
        return false;
    }
    let mut i = 5;
    while i * i <= n {
        if n % i == 0 || n % (i + 2) == 0 {
            return false;
        }
        i += 6;
    }
    true
}

Tre1z

2 months ago

2.90ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false;
    }
    if n == 2 || n == 3 {
        return true;
    }
    if n % 2 == 0 || n % 3 == 0 {
        return false;
    }
    let mut i = 5;
    while i * i <= n {
        if n % i == 0 || n % (i + 2) == 0 {
            return false;
        }
        i += 6;
    }
    true
}

Lvfalue

2 months ago

3.02ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n <= 1 {
        return false;
    }
    if n <= 3 {
        return true;
    }
    if n % 2 == 0 || n % 3 == 0 {
        return false;
    }
    let mut i = 5;
    while i * i <= n {
        if n % i == 0 || n % (i + 2) == 0 {
            return false;
        }
        i += 6;
    }
    true
}

Arpan Shingala

arpan-vs

2 months ago

4.11ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n == 1 {
        return false
    }
    let low = std::cmp::max( f64::sqrt(n as f64) as u32, 2);
    for i in low..n {
        if n % i == 0 {
            return false
        }
    }
    true
}

amdfxlucas

2 months ago

3.07ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n== 1
    {
        return false;
    }
    let low = std::cmp::max( f64::sqrt(n as f64 ) as u32, 2) ;
    
   
    for i in low..n
    {
        if n % i == 0
        {
         return  false;
        }
    }
    return true
}

GunGraveCpp

2 months ago

4.82ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    match n {
        0 | 1 => false,
        2 | 3 => true,
        _ => {
            let mid = (n as f32).sqrt().ceil() as u32;
            for i in 2..=mid {
                if n % i == 0 {
                    return false;
                }
            }
            return true;
        }
    }
}

manu3618

3 months ago

3.11ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n < 2 {
        return false
    }
    for x in 2..n {
        if n % x == 0 {
            return false
        }
    }
    true
}

aghia98

3 months ago

3.37ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    match n {
        0 | 1 => false,
        2 => true,
        _ => {
            let mut found = false;
            for i in 2..n {
                if n%i ==0 {
                    found = true;
                    break;
                }
            }
            !found
        }
    }
}

Christophe Pronier

chrpron

3 months ago

3.02ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here
    if n == 2 {
        return true
    } else if n<2 || n%2==0 {
        return false
    } else {
        for i in 3..n {
            if n%i == 0 {
                return false
            }
        }
        true
    }
}

Walter White

durgaprasad118

3 months ago

4.35ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    // Implement your code here 
    if n <=1 {
        return false;
    }
    if n==2 {
        return true;
    }
    let mut x =0;
    for i in 2..=n{
        if n%i ==0 && x<2 {
            x+=1;
        } 
    }
    if x <2 {
        return true
    }
    false
}

bzdula

3 months ago

3.03ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    match n {
        0 | 1 => false,
        2 | 3 => true,
        _ if n % 2 == 0 => false,
        _ => !(2..n).any(|i| n % i == 0),
    }
}

Ranjith Thangavel

RanjithECE24

3 months ago

2.82ms

81.43kb

pub fn is_prime(n: u32) -> bool {
    if n < 2 {
        return false;
    }
    for divisor in 2..=((n as f64).sqrt() as u32) {
        if n % divisor == 0 {
            return false;
        }
    }
    true
}