#include<bits/stdc++.h>
using namespace std;
int main(){
	long long int n,m1,m2,a[100010],ans=-1;
	int i,j;
	cin>>n;
	cin>>m1>>m2;
	for(i=1;i<=n;i++){
		cin>>a[i];
		for(j=1;j<=a[i]*m1;j++){
		if((a[i]*j)==m1)
		ans=j;
		continue;
	}
	}
	cout<<ans;
	return 0;
}