#include <iostream>
#include <cmath>
#include <limits>
using namespace std;
int main() {
int n;
unsigned long long m;
long long *A;
long long **Ab;
cin>>n>>m;
A = new long long [n];
Ab = new long long *[n];
for(int i = 0; i < n; i++){
cin>>A[i];
Ab[i] = new long long [m+1]{0};
}
for(int i = 1; i < n; i++){
Ab[i][0] = numeric_limits<int>::min();
}
for(unsigned long long j = 1; j < m+1; j++){
Ab[0][j] = max(A[0]*__builtin_popcount(j), Ab[0][j-1]);
}
for(int i = 1; i < n; i++){
for(unsigned long long j = 1; j < m+1; j++){
Ab[i][j] = max(A[i]*__builtin_popcount(j) + Ab[i-1][j-1], Ab[i][j-1]);
}
}
cout<<Ab[n-1][m];
for(int i = 0; i < n; i++){
delete [] Ab[i];
}
delete [] Ab;
delete [] A;
return 0;
}