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.

需要想明白的地方：进位，循环终止条件，if ＝＝ 10，还有就是注释那行不应该有

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