#include<bits/stdc++.h>
using namespace std;

int main(){
    long long int a,b,c,d,k;
    cin >> a >> b >> c >> d >> k;
    a %= k;
    b %= k;
    c %= k;
    d %= k;
    long long int ans = a*b+c-d;
    if(ans < 0) ans += (abs(ans)/k+1)*k;
    ans %= k;
    cout << ans << endl;
}