#include <bits/stdc++.h>
using namespace std;

int main(){
	int a[10], num[10],b[10],ans = 0;
	for(int i = 1;i <= 7;++i){
	    cin >> a[i] >> num[i];
	    
	}
	for(int i = 1;i <= 7;++i){
	    b[i] = a[i] + num[i];
	        if(b[i]>8){
	    	    ans = i;
	    	    break;
		}
	}
	cout << ans;
    return 0;
}