[leetcode] problem 66 – plus one

Given a non-negative integer represented as a non-empty array of digits, 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

No.1

No.2

Code

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public int[] plusOne(int[] digits) {
    for (int i = digits.length - 1; i >= 0; i--) {
        if (digits[i] != 9) {
            digits[i]++;
            return digits;
        }
        else
            digits[i] = 0;
    }

    int[] newDigit = new int[digits.length+1];
    newDigit[0] = 1;

    return newDigit;
}