#include<iostream>
using namespace std;

struct classtime {//这里使用一个结构体来分别表示在学校上课和妈妈安排上课的时间
	int school;
	int mom;
	int time_sum;
};
int main()
{
	classtime time[7];
	int count = 0, i, max = 0;
	for (i = 0; i < 7; i++)//输入上课时间
	{
		cin >> time[i].school >> time[i].mom;
		time[i].time_sum = time[i].school + time[i].mom;
		if (time[i].time_sum >= 8)
		{
			if (time[max].time_sum < time[i].time_sum)
				max = i;
			count++;
		}
	}
	max++;
	if (count == 0)
		cout << 0;
	else
		cout << max;
	return 0;
}