【LeetCode】66. Plus One

题目描述

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.

解题思路

大数加法。 由于只有9 + 1才会发生进位，所以特殊处理这个就好了。

AC代码

class Solution { public: vector<int> plusOne(vector<int>& digits) { vector<int> ans = digits; int i = ans.size() - 1; for (; i >= 0; --i) { if (ans[i] == 9) { ans[i] = 0; } else { ans[i] += 1; break; } } if (i < 0) ans.insert(ans.begin(), 1); return ans; } };