Plus One

public class Solution{
	public int[] plusOne(int[] digits){
		int flag = 1;
		int len = digits.length;
		
		for(int i = len - 1 ; i >= 0 ; i--){
			int sum = digits[i] + flag;
			flag = sum / 10;
			digits[i] = sum % 10;
		}
		if(flag == 1){
			int[] result = new int[len+1];
			result[0] = 1;
			System.arraycopy(digits,0,result,1,len);
			return result;
		}
		return digits;
	}
}