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.

题目含义：给定一个数组表示非负整数，其高位在数组的前面，对这个整数加1。

 1     public int[] plusOne(int[] digits) {
 2         int carry  =1;
 3         for (int i=digits.length-1;i>=0;i--)
 4         {
 5             int sum = carry + digits[i];
 6             digits[i] = sum%10;
 7             carry = sum/10;
 8         }
 9         if (carry ==0) return digits;
10         int[] result = new int[digits.length+1];
11         result[0] = carry;
12         for (int i=0;i<digits.length;i++)
13         {
14             result[i+1] = digits[i];
15         }
16         return result;        
17     }