Basic Math

Reverse Number is a staple interview problem: given a non-negative integer N, output the integer obtained by writing its digits in the opposite order. The task reinforces integer arithmetic, string handling, and edge-case thinking. 🔹 Problem Statement Input: A single non-negative integer N (0 ≤ N ≤ 1018). Output: The number obtained by reversing the … Read more

Count Digits is a classic warm-up problem: given a non-negative integer N, determine how many digits it contains. Although trivial to humans, it teaches loop control, integer math, and logarithms—skills that resurface in harder interview questions. 🔹 Problem Statement Input: A single non-negative integer N (0 ≤ N ≤ 1018). Output: The count of decimal … Read more