#include <iostream>
using namespace std;

int main()
{
	int mylist[7][2] = {};
	for (int i = 0; i < 7; i++) {
		for (int j = 0; j < 2; j++) {
			cin >> mylist[i][j];
		}
	}
	int turn = false;
	for (int i = 0; i < 7; i++) {
		if (mylist[i][0] + mylist[i][1] > 8) {
			turn = true;
			cout << i+1;
			break;
		}
	}
	if (!turn) {
		cout << "0" << endl;
	}


	
	return 0;
}