#include<iostream>
#include<cstdio>
#include<algorithm>
#include<string>
#include<cstring>
#include<cmath>
#include<set>
#include<map>
#include<vector>
#include<queue>
#include<unordered_map>
#include<stack>
#include<numeric>
using namespace std;
#define int long long

#define rep(i, a, b) for(int i = a;i <= b;i++)
#define pre(i, a, b) for(int i = a;i >= b;i--)

int n, a;
int b[100005];
int num[10];

signed main()
{
    cin >> n >> a;
    rep(i, 1, n) cin >> b[i];
    b[0] = b[n];
    b[n + 1] = b[1];
    rep(i, 1, n)
    {
        int shu = 0;
        if (b[i - 1] == 0) shu++;
        if (b[i] == 0) shu++;
        if (b[i + 1] == 0) shu++;
        num[shu]++;
    }
    int ans = n * 3;
    rep(i, 0, 3)
    {
        int p = min(a, num[i]);
        a -= p;
        num[i] -= p;
        ans -= p * i;
    }
    cout << ans << endl;
    return 0;
}