#include <iostream>

int main()
{
	long long a[4];

	int ans = 0;

	for (int i = 0; i < 4; ++i) {
		std::cin >> a[i];
	}

	ans = a[0] % a[3];

	for (int i = 1; i < 3; ++i) {
		ans = ans * a[i] % a[3];
	}
	std::cout << ans << std::endl;
}