#include<iostream>
#include<cstring>
#include<vector>
#include<algorithm>
using namespace std;
using LL = long long;

int main(){

#ifdef LOCAL
    freopen("data.in", "r", stdin);
    freopen("data.out", "w", stdout);
#endif

    cin.tie(0);
    cout.tie(0);
    ios::sync_with_stdio(0);

    int n, a;
    cin >> n >> a;
    vector<int> b(n);
    int ans = 0;
    for(int i = 0; i < n; i++){
        cin >> b[i];
        if (b[i] == 1) ans += 3;
    }
    vector<int> c(n);
    for(int i = 0; i < n; i++){
        c[i] = b[i] + b[(i + 1) % n] + b[(i - 1 + n) % n];
        c[i] = 3 - c[i];
    }
    vector<int> id(n);
    for(int i = 0; i < n; i++) id[i] = i;
    sort(id.begin(), id.end(), [&](int x, int y){
        return c[x] > c[y];
    });

    for(int i = 0; i < n - a; i++)
        ans += c[id[i]];
    cout << ans << '\n';

}