Leetcode#66||Plus One

public class Solution {
public int[] plusOne(int[] digits) {
if (digits == null || digits.length == 0) {
return digits;
}

int carry = 1;

for (int i = digits.length - 1; i >= 0 && carry > 0; i--) {
int sum = digits[i] + carry;
carry = sum / 10;
digits[i] = sum % 10;
}

if (carry == 0) {
return digits;
}

int[] result = new int[digits.length + 1];

result[0] = 1;

for (int i = 0; i < digits.length; i++) {
result[i + 1] = digits[i];
}

return result;
}
}