Description:
Given a non-empty array of digits representing a non-negative integer, plus one to the integer. The digits are stored such that the most significant digit is at the head of the list, and each element in the array contain a single digit. You may assume the integer does not contain any leading zero, except the number 0 itself. Example 1:
Input: [1,2,3]
Output: [1,2,4]
Explanation: The array represents the integer 123.
Example 2:
Input: [4,3,2,1]
Output: [4,3,2,2]
Explanation: The array represents the integer 4321.
解法：
模拟加法运算题，注意进位问题，尤其是从如99到100的问题。实现起来还是比较简单的，具体代码如下：1
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24class Solution {
public int[] plusOne(int[] digits) {
int[] tmp = new int[digits.length + 1];
int jinwei = 1;
for (int i = digits.length - 1; i >= 0; i--) {
int d = digits[i] + jinwei;
if (d == 10) {
jinwei = 1;
d = 0;
} else {
jinwei = 0;
}
tmp[i] = d;
}
if (jinwei == 1) {
tmp[0] = 1;
return tmp;
}
for (int i = 0; i < digits.length; i++) {
digits[i] = tmp[i];
}
return digits;
}
}