#include <stdio.h>
#include <string.h>
#include <stdlib.h>
int main()
{
	printf("Content-type: text/plain\n\n");
	if(!getenv("REMOTE_ADDR"))return 0;
	char* s=getenv("REMOTE_ADDR");
	if(getenv("HTTP_X_FORWARDED_FOR"))
	s=getenv("HTTP_X_FORWARDED_FOR");
	if(strchr(s,':')!=NULL)puts("6");
	else puts("4");
	return 0;
}