#include"bits/stdc++.h"
#define ll long long
#define cl(x) scanf("%lld",&x)
#define pl(x) printf("%lld\n",x)
using namespace std;
int main()
{
    ll a,b,c,d;
    while(scanf("%lld%lld%lld%lld",&a,&b,&c,&d)==4)
    {
        ll ans=0;
        ll a1,a2,a3;
        a1=(b/2018)-((a-1)/2018);
        a1*=d-c+1;

        a2=b/1009-(a-1)/1009-(b/2018-(a-1)/2018);
        a2*=d/2-(c-1)/2;

        a3=b/2-(a-1)/2-(b/2018-(a-1)/2018);
        a3*=d/1009-(c-1)/1009;

        ans+=(b-a+1-(b/2-(a-1)/2)-(b/1009-(a-1)/1009)+(b/2018-(a-1)/2018))*(d/2018-(c-1)/2018);
        ans+=a1+a2+a3;

        pl(ans);
    }
}