#include <iostream>
using namespace std;

int main() {
    int n, x;
	cin >> n >> x;

	int a[n + 1];

	for (int i = n; i >= 0; --i)
	{
		cin >> a[i];
	}

	int s = a[n]; // тут s = a0

	for (int i = 1; i <= n; ++i)
	{
		s *= x;
		s += a[n-i];
	}
	cout << s << endl;

    return 0;
}