#include<bits/stdc++.h>
using namespace std;
int main(){
    int a,b,c=0,day1=0,day2=0;
    for(int i=1;i<=7;i++){
    	day1++;
    	cin>>a>>b;
    	int j=a+b;
    	if(j>8&&j>c) day2=day1;
	}
    cout<<day2;
}