![]()
#include<bits/stdc++.h>
#define forn(i, n) for (int i = 0 ; i < int(n) ; i++)
#define fore(i, s, t) for (int i = s ; i < (int)t ; i++)
#define fi first
#define se second
#define all(x) x.begin(),x.end()
#define pf2(x,y) printf("%d %d\n",x,y)
#define pf(x) printf("%d\n",x)
#define each(x) for(auto it:x) cout<<it<<endl;
#define pii pair<int,int>
#define sc(x) scanf("%d",&x)
using namespace std;
typedef long long ll;
const int maxn=2e5+5;
const int maxm=2e5+5;
const int inf=1e9;
ll len(ll l,ll r){
return r-l;
}
int main(){
ll la,ra,ta,lb,rb,tb;
cin>>la>>ra>>ta>>lb>>rb>>tb;
ll g=__gcd(ta,tb),ans=0;
if(abs(la-lb)%g) {
ll d=(lb-la)%g;
if(d<0) d+=g;
ans=max(ans,min(d+len(lb,rb),len(la,ra))-max(0ll,d)+1);
d=g-d;
ans=max(ans,min(len(lb,rb),d+len(la,ra))-max(0ll,d)+1);
}
else {
ans=min(len(la,ra)+1,len(lb,rb)+1);
}
cout<<ans<<endl;
}