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.
Follow up:
Could you do it without any loop/recursion in O(1) runtime?
题目描写叙述:给出一个数组,不断地切割数字,直到这个数字是一个数字为止。题目非常easy,直接上代码。
代码实现:
class Solution { public: int addDigits(int num) { while(num<10) { return num; } int s=0; while(num>0) { s+=num%10; num/=10; } return addDigits(s); } };