#include<bits/stdc++.h>
#define pii pair<int,int>
#define mp make_pair
using namespace std;
int n,a,ans;
int b[100005];
int cnt[4];
signed main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin>>n>>a;
	for(int i=1;i<=n;i++){
		cin>>b[i];
	}
	for(int i=1;i<=n;i++){
		cnt[b[i%n+1]+b[i]+b[(i+n-2)%n+1]]++;
	}
	ans=(n-a)*3;
	for(int i=3;i>=0&&a>0;i--){
		ans+=i*min(a,cnt[i]);
		a-=min(a,cnt[i]);
	}
	cout<<ans<<'\n';
	return 0;
}