#include <bits/stdc++.h>
using namespace std;
#define int long long
signed main(){
    int A,B,C,D,X;
    cin>>A>>B>>C>>D>>X;
    int ans = 0;
    for(int i=A;i<=B;i++)for(int j=C;j<=D;j++){
        ans = max(ans,(i+j)%X);
    }
    cout<<ans<<endl;
}