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Given a non-negative number represented as an array of digits, plus one to the number.
The digits are stored such that the most significant digit is at the head of the list.
题意：给定一个由数组表示大整数，数组的每一个元素对应该数的十进制表示的每一位，对该数进行加 1 操作
思路：高精度加法
复杂度：时间：O(n)
vector<int> plusOne(vector<int> &digits){
int carry = 1;
for(auto it = digits.rbegin(); it != digits.rend(); ++it){
int tmp = *it + carry;
*it = tmp % 10;
carry = tmp / 10;
if(!carry) break;
}
if(carry) digits.insert(digits.begin(), carry);
return digits;
}原文：http://blog.csdn.net/zhengsenlie/article/details/38915083