include<bits/stdc++.h>
using namespace std; struct f{
int shangke;
int mamadeke;
}; int main(){
f a[10];
for(int i=1;i<=7;i++){
cin>>a[i].shangke>>a[i].mamadeke;
if(a[i].shangke+a[i].mamadeke>8){
cout<<i;
return 0;
}
}
cout<<"0";
return 0;
}