#include <iostream>
#include <vector>
#include <algorithm>
#include <numeric>

using namespace std;

int main(){
	int n, v;
	cin >> n >> v;
	vector<long long> c(n);
	for (int i = 0; i < n; ++i) cin >> c[i];

	partial_sum(c.begin(), c.end(), c.begin());

	const int N = 300;
	vector<long long> dp(N + 10, 1e18);
	dp[0] = 0;
	for (int i = 0; i < n; ++i){
		for (int j = 0; j < N - i; ++j){
			dp[i + 1 + j] = min(dp[i + 1 + j], dp[j] + c[i]);
		}
	}
	for (int i = N; i >= 0; --i) dp[i] = min(dp[i], dp[i + 1]);

	long long base = c.back();
	v = max(0, v - n);

	long long ans = 1e18;
	for (int i = 0; i < n; ++i){
		ans = min(ans, v / (i + 1) * c[i] + dp[v % (i + 1)]);
	}
	cout << base+ans << endl;

	return 0;
}