#include<bits/stdc++.h>
using namespace std;
struct{
	int x , y;
}a[15];
int n;
long long gcd(long long a , long long b){
	if(a % b == 0) return b;
	return gcd(b , a% b);
}
long long lcm(long long a , long long b){
	return a / gcd(a , b) * b;
}
int main(){
	cin >> n;
	for(int i = 1 ; i <= n ; i++){
		cin >> a[i].x >> a[i].y;
	}
	long long js = a[1].x;
	long long cnt = a[1].y;
	for(int i = 2 ; i <= n ; i++){
		while(cnt % a[i].x != a[i].y){
			cnt += js;
		}
		js = lcm(js , a[i].x);
	}
	cout << cnt;
}

TLE了4个，RE了1个，有没有优化方法？