#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using ld = long double;

const ll mod = 1000000007;
ll a, b, c, k, x, y;

int main() {
  cin >> a >> b >> c >> k;
  x = a * b % mod;
  x = x * c % mod;
  y = pow_mod(2, k, mod - 1);
  cout << pow_mod(x, y, mod) << endl;
  return 0;
}