1031. Hello World for U (20)

#include <iostream>
#include <string.h>

using namespace std;

int main()
{
	char s[100];
	gets(s);

	int n1, n2, n = strlen(s), flag = 0;
	for(n2 = 3; n2 <= n; n2++)
	{
		for(n1 = n2; n1 >= 1; n1--)
		{
			if(n1 * 2 + n2 - 2 == n)
			{
				flag = 1;
				break;
			}
		}

		if(flag == 1)
		{
			break;
		}
	}

	int i, j;
	for(i = 0; i <= n1 - 2; i++)
	{
		printf("%c", s[i]);

		for(j = 1; j <= n2 - 2; j++)
		{
			printf(" ");
		}

		printf("%c\n", s[n - i - 1]);
	}

	for(i = n1 - 1; i <= n1 + n2 - 2; i++)
	{
		printf("%c", s[i]);
	}
	
	printf("\n");

	system("pause");
	return 0;
}