Problem:
Score : 100 points

Problem Statement

You are given two integers A and B as the input. Output the value of A + B.

However, if A + B is 10 or greater, output error instead.

Constraints

A and B are integers.

1 ≤ A, B ≤ 9

Input

Input is given from Standard Input in the following format:

A B

Output

If A + B is 10 or greater, print the string error (case-sensitive); otherwise, print the value of A + B.

Sample Input 1

6 3

Sample Output 1

9

Sample Input 2

6 4

Sample Output 2

error

Solution in C (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>
#include<stdlib.h>
#include<string.h>

int main(int argc, char *argv[])
{
	int i, j, len;
	int flag = 0;
	char input[30];

	scanf("%s", input);
	len = strlen(input);


	for (i = 1; i < len; i++) {
		for (j = i + 1; j < len; j++) {
			if (input[i] == input[j]) {
				printf("no");
				exit(0);
			}
		}
	}
	printf("yes");

	return(0);
}