又王记\n了搞了一次PE。。。/(ㄒoㄒ)/~~
#include <iostream>
#include <stdio.h>
using namespace std;

int main() {
	int N;
	while(1){
		scanf("%d", &N);
		if(N == 0) return N;
		int arv = 2147483647;
		for(int i = 0; i < N; i++){
			int T, V;
			scanf("%d%d", &V, &T);
			if(T < 0) continue;
			int temp = 16199/V + T + 1;
			if(temp < arv) arv = temp;
		}
		printf("%d", arv);
	}
	return 0;
}