66. 加一

66. 加一

class Solution {
    public int[] plusOne(int[] digits) {
        List<Integer> list = new ArrayList<>();
        int flag = 0;
        for (int i = digits.length - 1; i>= 0; i--) {
            int curNumber = 0;
            if (i == digits.length - 1) {
                curNumber = (digits[i] + flag + 1) % 10;
                flag = (digits[i] + flag + 1) / 10;
            } else {
                curNumber = (digits[i] + flag) % 10;
                flag = (digits[i] + flag) / 10;
            }
            list.add(curNumber);
        }
        if (flag == 1) {
            list.add(1);
        }
        int size = list.size();
        int[] ans = new int[size];
        int index = size - 1;
        for (Integer num : list) {
            ans[index] = num;
            --index;
        }
        return ans;
    }
}