#include "bits/stdc++.h" using namespace std; #define fastcin {\ cin.tie(0);\ ios::sync_with_stdio(false);\ } #define rep(i, a, b) for(int i = a; i < b; i++) #define rrep(i, a, b) for(int i = a; i >= b; i--) #define fore(i, a) for(auto &i:a) #define print(x) cout << x << "\n" #define SORT(a, n) sort(a, a+n); #define REVERSE(a,n) reverse(a,a+n); #define VSORT(v) sort(v.begin(), v.end()); #define VREVERSE(v) reverse(v.begin(), v.end()); #define MOD 1000000007 #define yes "YES" #define no "NO" typedef long long ll; typedef vector vi; typedef vector vvi; typedef vector vll; int main() { fastcin; ll a, b, c, d, ans; cin >> a >> b >> c >> d; ans = (((a*b)%d)*c)%d; print(ans); return 0; }