1001. A+B Format (20)

#include "stdafx.h"
#include <iostream>
#include <algorithm>
#include <queue>
#include <stdlib.h>
#include <string.h>

using namespace std;

int main()
{
	int a, b;
	scanf("%d%d", &a, &b);

	int n = a + b;
	if(n < 0)
	{
		printf("-");
		n = -n;
	}

	char s[20];
	sprintf(s, "%d", n);

	int len = strlen(s), i, index;
	for(i = 0; i < len; i++)
	{
		printf("%c", s[i]);
		index = len - i;

		if(index > 3 && index % 3 == 1)
		{
			printf(",");
		}
	}

	printf("\n");

	system("pause");
	return 0;
}