#include<bits/stdc++.h>
#include<unordered_map>
#include<unordered_set>
typedef long long ll;
typedef long double ld;
#define debug(a) cout<<a<<'\n'
#define Pll pair<ll,ll>
#define PII pair<int,int>
#define ft first
#define sd second
#define vec vector
#define pushk push_back
#define pl p<<1
#define pr p<<1|1
using namespace std;
const int N = 2e5 + 10, M = 1e4 + 10, mod = 1e9 + 7;
const ll inf = 1e18;
const ld eps = 1e-13;
int mov[4][2] = { {0,1},{1,0},{-1,0},{0,-1} }, dx, dy, _ = 1, __ = 1;
void bout(bool f) {
	if (f)cout << "Yes\n";
	else cout << "No\n";
}
ll n, m, k;
int a[N];

void ini() {
}
void solve() {
	cin>>n>>m;
	for(int i=1;i<=n;++i)cin>>a[i];
	map<int,int>mp;
	int x;
	for(int i=2;i<n;++i){
		x=a[(i+n-2)%n+1]+a[i]+a[i%n+1];
		if(x==3)++mp[3];
		else if(x==2)++mp[2];
		else if(x==1)++mp[1];
		else ++mp[0];
	}
	int ans=3*n;
	for(int i=3;i>=0;--i){
		if(mp[i]>=m){
			ans-=m*(3-i);
			break;
		}else{
			ans-=mp[i]*(3-i);
			m-=mp[i];
		}
	}
	cout<<ans;
}

int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
#ifndef ONLINE_JUDGE
	streambuf* cinbackup = cin.rdbuf(), * coutbackup = cout.rdbuf();
	ifstream fin("in.txt");
	ofstream fout("out.txt");
	cin.rdbuf(fin.rdbuf());
	cout.rdbuf(fout.rdbuf());
#endif
	//cin >> _;
	__ = _;
	ini();
	while (_--) {
		solve();
	}
	return 0;
}