#include<bits/stdc++.h>
using namespace std;
#include<atcoder/all>
using namespace atcoder;
using ll = long long;
int n;
vector<ll> a;
vector<ll> b;

void solve(){
	auto p = crt(a,b);
	if(p.first==0&&p.second == 0){
		cout<<-1<<endl;
	}else{
		if(p.first)
		cout<<p.first<<endl;
		else cout<<lcm(lcm(b[0],b[1]),b[2])<<endl;
	}
}

signed main(){
	cin.tie(nullptr);
	ios::sync_with_stdio(false);
	n =3;
	a = vector<ll>(n);
	b = vector<ll>(n);
	for(int i = 0;i<n;i++)cin >> a[i] >> b[i];

	solve();
}