#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <chrono>
#include <cmath>
#include <complex>
#include <deque>
#include <forward_list>
#include <fstream>
#include <functional>
#include <iomanip>
#include <ios>
#include <iostream>
#include <limits>
#include <list>
#include <map>
#include <memory>
#include <numeric>
#include <optional>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <tuple>
#include <type_traits>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>


int main() {
    int N, A;
    std::cin >> N >> A;
    std::vector<int> B(N);
    for(int i = 0; i < N; i++) std::cin >> B[i];
    std::vector<int> cnt(4);
    for(int i = 0; i < N; i++) {
        int c = B[i] + B[(i + 1) % N] + B[(i + 2) % N];
        c = 3 - c;
        cnt[c]++;
    }
    int pena = 0;
    for(int i = 0; i < 4; i++) {
        int remain = std::min(cnt[i], A);
        A -= remain;
        pena += i * remain;
    }
    std::cout << N * 3 - pena << std::endl;
}