1、题目
Given a non-negative integer num, repeatedly add all its digits until the result has only one digit.
For example:
Given num = 38, the process is like: 3 + 8 = 11, 1 + 1 = 2. Since 2 has only one digit, return it.
2、代码实现
public class Solution { public int getAllSum(int val) { int sum = 0; while (val > 0) { sum += val % 10; val /= 10; } return sum; } public int addDigits(int num) { if (num <= 0) return 0; while (num >= 10) { num = getAllSum(num); } return num; } }
