_1342.java

package com.fishercoder.solutions;

/**
 * 1342. Number of Steps to Reduce a Number to Zero
 *
 * Given a non-negative integer num, return the number of steps to reduce it to zero.
 * If the current number is even, you have to divide it by 2, otherwise, you have to subtract 1 from it.
 *
 * Example 1:
 * Input: num = 14
 * Output: 6
 * Explanation:
 * Step 1) 14 is even; divide by 2 and obtain 7.
 * Step 2) 7 is odd; subtract 1 and obtain 6.
 * Step 3) 6 is even; divide by 2 and obtain 3.
 * Step 4) 3 is odd; subtract 1 and obtain 2.
 * Step 5) 2 is even; divide by 2 and obtain 1.
 * Step 6) 1 is odd; subtract 1 and obtain 0.
 *
 * Example 2:
 * Input: num = 8
 * Output: 4
 * Explanation:
 * Step 1) 8 is even; divide by 2 and obtain 4.
 * Step 2) 4 is even; divide by 2 and obtain 2.
 * Step 3) 2 is even; divide by 2 and obtain 1.
 * Step 4) 1 is odd; subtract 1 and obtain 0.
 *
 * Example 3:
 * Input: num = 123
 * Output: 12
 *
 * Constraints:
 * 0 <= num <= 10^6
 * */
public class _1342 {
    public static class Solution1 {
        public int numberOfSteps(int num) {
            int steps = 0;
            while (num != 0) {
                if (num % 2 == 0) {
                    num /= 2;
                } else {
                    num--;
                }
                steps++;
            }
            return steps;
        }
    }
}