#include <bits/stdc++.h>
#include <atcoder/all>

using std::cin;
using std::cout;
using namespace atcoder;
using mint = modint1000000007;
using ll = long long;

int main() {
	ll a, b, c, k;
	cin >> a >> b >> c >> k;
	
	mint x = mint(a) * mint(b) * mint(c);
    ll p = pow_mod(2, k, 1000000006);
	mint ans = x.pow(p);
	
	cout << ans.val() << '\n';
	
	return 0;
}