#include <iostream>
#include <cstdio>

using namespace std;

//霍納法則
/*
輸入：
5 3
2 -1 3 1 -5
*/
int x;
int xishu[11];

int cal(int num)
{
	int i,answer=0;
	for(i=num;i;i--)
	{
		//霍納法則公式：
		//p(x)=(...(An*X+An-1)*X+...)*X+A0
		answer=answer*x+xishu[i];
	}
	return answer;
}

int main()
{
	int num,i;
	scanf("%d%d",&num,&x);
	i=num;
	for(;i;i--)
		scanf("%d",&xishu[i]);//從高次項(xiàng)系數(shù)開(kāi)始輸
	cout<<cal(num)<<endl;
	return 0;
}