#include<iostream>
#include<cstdio>
#include<algorithm>
using namespace std;
#define MAXN 10000
struct dd{
	int left,right;
}jie[12000];
struct dt{
	int a[100002];
}ans,k;
int n;
bool comp(const dd & a,const dd & b){
	return a.left*a.right<b.left*b.right;
}
void mul(int h){
	ans.a[0]+=2;
	for(int i=1;i<=ans.a[0];++i)
	 ans.a[i]=ans.a[i]*h;
	for(int i=1;i<=ans.a[0];++i){
		ans.a[i+1]+=ans.a[i]/MAXN;
		ans.a[i]%=MAXN;
	}
	while(ans.a[0]>=1&&ans.a[ans.a[0]]==0) ans.a[0]--;
}
dt muk(dt m,int d){
	for(int i=m.a[0];i>=1;--i){
		if(i!=1) m.a[i-1]=(m.a[i]%d)*MAXN+m.a[i-1];
		m.a[i]/=d;
	}
	while(m.a[0]>=1&&m.a[m.a[0]]==0) m.a[0]--;
	return m;
}
int main(){
    freopen("kinggame.in","r",stdin);
	freopen("kinggame.out","w",stdout);
	scanf("%d",&n);
	scanf("%d%d",&jie[0].left,&jie[0].right);
	for(int i=1;i<=n;++i) scanf("%d%d",&jie[i].left,&jie[i].right);
	sort(jie+1,jie+n+1,comp);
    ans.a[0]=1; ans.a[1]=1;
	mul(jie[0].left);
	for(int i=1;i<=n-1;++i) mul(jie[i].left);
	k=muk(ans,jie[n].right);
	if(k.a[k.a[0]]==0) puts("1");
	else{
		cout<<k.a[k.a[0]];
		for(int i=k.a[0]-1;i>=1;--i) printf("%04d",k.a[i]);
	}
}