#include <iostream>
#include <cstdio>
#include <algorithm>
#include <vector>
using namespace std;

#define SZ(a) (int)(a).size()
using ll = long long;

int main() {
    cin.sync_with_stdio(false);
    int n;
    int m;
    cin >> n >> m;
    vector<int> foods;
    for (int i = 0; i < n; i++) {
        int x;
        cin >> x;
        foods.push_back(x);
    }
    vector<int> ms;
    for (int m1 = m; m1 > 0; m1 = m1 * 2 / 3) {
        ms.push_back(m1);
    }
    int k = SZ(ms);
    vector<int> zeros(k, 0);
    vector<int> ones(k, 0);
    int two = 0;
    for (int i = 0; i < n; i++) {
        auto zeros_ = zeros;
        zeros[0] = max(two, ones[0]) + min(foods[i], m);
        for (int j = 1; j < k; j++) {
            zeros[j] = max(zeros_[j - 1], ones[j]) + min(foods[i], ms[j]);
        }
        for (int j = 0; j < k; j++) {
            two = max(two, ones[j]);
        }
        ones = zeros_;
        // printf("Iteration %d\n", i);
        // for (int j = 0; j < k; j++) {
        //     printf("%d%c", zeros[j], " \n"[j == k - 1]);
        // }
        // for (int j = 0; j < k; j++) {
        //     printf("%d%c", ones[j], " \n"[j == k - 1]);
        // }
        // printf("%d\n", two);
        // puts("");
    }
    int ans = two;
    for (int j = 0; j < k; j++) {
        ans = max(ans, zeros[j]);
        ans = max(ans, ones[j]);
    }
    printf("%d\n", ans);
    return 0;
}