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Find the First Palindrome


Find the First Palindrome

In this challenge, you will demonstrate your understanding of control flow in Rust. The task involves finding the first palindrome number in a given range.

What's a palindrome?

A palindrome is a number that reads the same backward as forward. This exercise will require you to iterate through the range, check each number to see if it is a palindrome, and return the first palindrome found. You can use any control flow construct to solve this problem.

Palindromes are fascinating numbers, and finding them within a range will require efficient control flow logic to ensure you identify the first one accurately.

Your task

You need to write a function, find_first_palindrome(start: i32, end: i32) -> Option<i32>, that takes two integer arguments start and end. The function should return the first palindrome number within the range (inclusive). If there are no palindromes in the range, it should return None.


  • The function should iterate through the numbers from start to end.
  • It should check each number to determine if it is a palindrome.
  • The function should return the first palindrome found, or None if no palindromes exist in the range.
  • You must handle cases where start may be greater than end.


let result = find_first_palindrome(10, 30);
assert_eq!(result, Some(11)); // 11 is the first palindrome in the range
let result = find_first_palindrome(100, 105);
assert_eq!(result, Some(101)); // 101 is the first palindrome in the range
let result = find_first_palindrome(123, 130);
assert_eq!(result, None); // No palindromes in this range

Did you know?

Did you know that palindromes are not just limited to numbers? They are found in words, phrases, and even DNA sequences! For example, the word "racecar" is a palindrome, as it reads the same backward and forward. Palindromes are fascinating in various fields, including mathematics, literature, and biology, where they often have unique properties and significance.


  • To check if a number is a palindrome, convert it to a string and compare it with its reverse.
  • You can get the reverse by using the rev() method on a char.
  • You can get the chars in a string by using the chars() method on a String
  • Use a loop, iterator, or any other control flow construct to check each number in the range until a palindrome is found or the range is exhausted.
  • Remember to handle the case where start is greater than end by swapping the values if necessary.