Little Jhool and psychic powers

#include<stdio.h>
#include <string.h>
#define pf printf
#define sf scanf
int main()
{ 
int i,c=0,j;
char s[1000];
sf("%s",s);
int n = strlen(s);
for(i=0;i<n;i++)
{
		if(s[i]=='0' || s[i]=='1')
		{		char x = s[i];
				for(j=i+1;j<=i+6;j++)
					{if(s[j]==x)
							{c++;}
 
					}
 
					if(c==5)
					{
						pf("Sorry, sorry!");
						return 0 ;
					}
					else
								c=0;
		}
 
}
 
pf("Good luck!");
 
}