#include <iostream>
#include <cstdio>
#include <string>
#include <sstream>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <stack>
#include <cmath>
#include <algorithm>
#include <cstring>
#include <ctime>
#include <cassert>
#include <random>
using namespace std;
using ll = long long;
const ll INF = 1e18;
int get_num_ones(ll n) {
int ones = 0;
while (n > 0) {
if (n%2 == 1) {
++ones;
}
n /= 2;
}
return ones;
}
int main() {
ios_base::sync_with_stdio(0);
int n;
ll m;
cin >> n >> m;
vector<ll> a(n);
for (int i = 0; i < n; ++i) {
cin >> a[i];
}
vector<int> ones(m+1);
for (int i = 0; i <= m; ++i) {
ones[i] = get_num_ones(i);
}
vector<vector<ll>> f(2, vector<ll>(m+1, -INF));
int cur = 1;
for (int i = 0; i < n; ++i) {
for (int j = 0; j <= m; ++j) {
f[cur][j] = -INF;
}
for (int j = i; j <= m; ++j) {
if (i == 0) {
f[cur][j] = a[i]*ones[j];
} else {
f[cur][j] = max(f[cur][j], f[1-cur][j-1] + a[i]*ones[j]);
}
}
for (int j = 1; j <= m; ++j) {
f[cur][j] = max(f[cur][j], f[cur][j-1]);
}
cur = 1-cur;
}
cout << f[1-cur].back() << endl;
return 0;
}