#include <iostream>
#include <cmath>
using namespace std;

int main() {
    int A, B, C, D, M;
    cin >> A >> B >> C >> D >> M;
    
    int max = -1;
    
    for (int x=A; x <= B; x++) {
        for (int y=C; y <= D; y++) {
            max = (max < fmod(x+y, M)) ? fmod(x+y, M) : max;
        }
    }
    
    cout << max << endl;
}