LeetCode 66. Plus One

Given a non-negative integer represented as a non-empty array of digits, plus one to the integer.

You may assume the integer do not contain any leading zero, except the number 0 itself.

The digits are stored such that the most significant digit is at the head of the list.

---

 

Seen this question in a real interview before?  

Yes

No

 

 

这道题要求vector中表示一个整数的各个位数，末尾 + 1，要求返回计算之后的结果， 思路很直接，不难，需要注意的是讨论进位的情况，代码如下：

class Solution {
public:
    vector<int> plusOne(vector<int>& digits) {
        int carry = 1;
        int len = digits.size();
        for (int i = len-1; i >=0 ;i--)
        {
            digits[i] += carry;
            if (digits[i] == 10)
            {
                 digits[i] = 0;
                 carry = 1;
            }
            else
            {
                //carry = 0;
                return digits;
            }
        }
        digits.insert(digits.begin(),1);
        return digits;
    }
};