#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
#define exit exit(false)
//#define here() cerr << "herewego\n";
#define show(x) cerr << #x << ": " << x << '\n';
#define int long long
//#define double long double
#define all(a) a.begin(), a.end()
#define whole(a, p, q) a+p, a+p+q
#define ioio() ios_base::sync_with_stdio (0); cin.tie (0); cout.tie (0);
using namespace std;
//using namespace __gnu_pbds;
//typedef tree <int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;
const int mxsz = 1e5 + 7;
int n, k, a[mxsz], t[mxsz * 4], mn = LLONG_MAX;
void build (int v, int tl, int tr) {
if (tl == tr) {
t[v] = a[tl];
return;
}
int tm = (tl + tr) >> 1;
int lf = (v << 1);
int rg = (v << 1 | 1);
build (lf, tl, tm);
build (rg, tm+1, tr);
t[v] = max (t[lf], t[rg]);
}
int get (int v, int tl, int tr, int l, int r) {
if (l <= tl && tr <= r) {
return t[v];
}
if (tr < l || r < tl) {
return 0;
}
int tm = (tl + tr) >> 1;
int lf = (v << 1);
int rg = (v << 1 | 1);
return max(get (lf, tl, tm, l, r), get (rg, tm+1, tr, l, r));
}
int get (int l, int r) {
return get (1, 1, n, l, r);
}
signed main () { ioio();
cin >> n >> k;
for (int i = 1; i <= n; i++) {
cin >> a[i];
}
build (1, 1, n);
// if (k == 1) {
// cout << get (1, n);
// exit;
// }
if (n <= 20) {
for (int ma = 1; ma <= (1 << (n-1)); ma++) {
vector <int> po;
for (int i = 0; i < n-1; i++) {
if ((1 << i) & ma) {
po.push_back(i+1);
}
}
if (po.size() == k-1) {
po.push_back(n);
int sm = 0;
sm += get(1, po[0]);
for (int i = 1; i < po.size(); i++) {
sm += get(po[i-1] + 1, po[i]);
}
// cerr << sm << ' ' << po[0] << ' ' << po[1] << '\n';
mn = min (mn, sm);
}
}
cout << mn;
exit;
} else {
cout << "wronganswer";
}
}
