#include<bits/stdc++.h>
using namespace std;
struct idioms{
	string s1,s2,s3,s4;
	int r1=0,c1=1,r2=1,c2=0; 
}a[10005];
int n;
int main(){
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>a[i].s1>>a[i].s2>>a[i].s3>>a[i].s4;
	} 
	for(int i=1;i<=n;i++){
		for(int j=1;j<=n;j++){
			if(j==i)continue;
			if(a[i].s1==a[j].s1)a[i].c1++;
			if(a[i],s1==a[j].s4)a[i].r1++;
			if(a[i].s4==a[j].s1)a[i].c2++;
			if(a[i].s4==a[j].s4)a[i].r2++;
		}
	}
	srand(time(0));
	cout<<rand()%10;
	return 0;
}