#include<stdio.h>
long a,b,c,s,S,i,n;
int main()
{
	freopen("inundatii.in","r",stdin);
	freopen("inundatii.out","w",stdout);
	scanf("%ld",&n);
	for (i=1;i<=n;i++)
	{
		scanf("%ld%ld%ld",&a,&b,&c);
		if (s==0)
		s=a+b+c;
		else
		S=a+b+c;

	}
	if (n==2) printf("%ld\n",s-S+3);
	else
	printf("0\n");


	return 0;
}