加一

public class Solution {
    /**
     * @param digits a number represented as an array of digits
     * @return the result
     */
    public int[] plusOne(int[] digits) {
        int carry = 1;
        for (int i = digits.length - 1; i >= 0; i--) {
            int sum = digits[i] + carry;
            carry = sum / 10;
            digits[i] = sum % 10;
        }
        
        if (carry != 0) {
            int[] temp = new int[digits.length + 1];
            temp[0] = carry;
            for (int i = 0; i < digits.length - 1; i++) {
                temp[i + 1] = digits[i];
            }
            return temp;
        }
        return digits;
    }
}