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Easy CHALLENGE

Reverse Number

Given an integer, reverse its digits.

Logical Approach_

1
Initialize reversed_num = 0.
2
While input num is not 0:
3
- Get last digit using num % 10.
4
- Multiply reversed_num by 10 and add the digit.
5
- Remove last digit from num using floor division by 10.

Variations Hub_

Reverse a number and handle 32-bit integer overflow (LeetCode variant).
Check if reversing a number results in the same number (another way for palindrome).
Implementation Protocol (JS)
function reverseNumber(num) {
  let reversed = 0;
  let sign = num < 0 ? -1 : 1;
  num = Math.abs(num);
  
  while (num > 0) {
    reversed = (reversed * 10) + (num % 10);
    num = Math.floor(num / 10);
  }
  
  return reversed * sign;
}

Line-by-Line Breakdown_

Point 1

Line 3-4: Handle negative numbers by storing the sign and using absolute values.

Point 2

Line 7: Shift existing reversed digits left by multiplying by 10 and add the new digit.

Point 3

Line 8: Update input number by removing the unit place digit.

Point 4

Line 11: Restore the original sign to the reversed result.

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Execute in the interactive playground for deep analysis.