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

using LL = long long;

const int mod = 1e9 + 7;

LL pow_mod(LL x, LL p, int mod){
	LL s = 1;
	for(; p; p>>=1){
		if(p & 1)	s = s * x % mod;
		x = x * x % mod;
	}
	return s;
}

int main(){
	LL a, b, c, K;
	scanf("%lld %lld %lld %lld", &a, &b, &c, &K);
	printf("%lld\n", pow_mod(a * b % mod * c % mod, pow_mod(2, K, mod - 1), mod));
	
	return 0;
}