#include <bits/stdc++.h>

 
 
typedef long long ll;
 
using namespace std;

#define rep(i,n)  for(int i=0;i<(n);i++)
const ll INF=1000000000000000000;

ll mod(ll a,ll m){
    return (a%m+m)%m;
}

ll extGcd(ll a,ll b,ll &p,ll &q){
    if(b==0){p=1;q=0;return a;}
    ll d=extGcd(b,a%b,q,p);
    q-=a/b*p;
    return d;
}

pair<ll,ll> ChineseRem(const vector<ll> &b,const vector<ll> &m){
    ll r=0,M=1;
    for(int i=0;i<(int)b.size();++i){
        ll p,q;
        ll d=extGcd(M,m[i],p,q);
        if((b[i]-r)%d!=0)return make_pair(0,-1);
        ll tmp=(b[i]-r)/d*p%(m[i]/d);
        r+=M*tmp;
        M*=m[i]/d;
    }
    return make_pair(mod(r,M),M);
    
}
ll gcd(ll a, ll b)
{
   if (a%b == 0)
   {
       return(b);
   }
   else
   {
       return(gcd(b, a%b));
   }
}

ll lcm(ll a, ll b)
{
   return a * b / gcd(a, b);
}


int main(){
    vector<ll> X(3),Y(3);
    
    for(int i=0;i<3;i++){
        cin>>X[i];
        cin>>Y[i];
    }

    
    if(X[0]==X[1]&&X[1]==X[2]&&X[2]==0){
        cout<<lcm(Y[0],lcm(Y[1],Y[2]))<<endl;
    }else {
        pair<ll,ll> pr=ChineseRem(X,Y);
        if(pr.second==-1){
            cout<<-1<<endl;
        }else{
            cout<<pr.first<<endl;
        }
    }
    
    
    
}