#include <bits/stdc++.h>
using namespace std;

template<typename T>
vector<pair<T,long long>> RLE(vector<T> &A){
    if(A.size() == 0) return {};
    vector<pair<T,long long>> ret;
    T back = A.at(0);
    long long streak = 1;
    for(int i=1; i<A.size(); i++){
        if(back == A.at(i)) streak++;
        else{
            ret.push_back({back,streak});
            back = A.at(i); streak = 1;
        }
    }
    ret.push_back({back,streak});
    return ret;
}
vector<pair<char,long long>> RLE(string &s){
    if(s.size() == 0) return {};
    vector<pair<char,long long>> ret;
    char back = s.at(0);
    long long streak = 1;
    for(int i=1; i<s.size(); i++){
        if(back == s.at(i)) streak++;
        else{
            ret.push_back({back,streak});
            back = s.at(i); streak = 1;
        }
    }
    ret.push_back({back,streak});
    return ret;
}

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    long long N,K; cin >> N >> K;
    vector<int> A(N);
    for(auto &a : A) cin >> a;
    A.insert(A.begin(),0),A.push_back(0);
    auto B = RLE(A);
    long long answer = 0;
    for(int i=1; i<A.size(); i++) answer += abs(A.at(i)-A.at(i-1));

    set<tuple<int,int,int>> S;
    priority_queue<tuple<int,int,int>,vector<tuple<int,int,int>>,greater<>> Q;
    for(int i=0,s=0; i<B.size(); i++){
        S.insert({s,B.at(i).second,B.at(i).first});
        if(i && i+1 < B.size() && B.at(i-1).first < B.at(i).first && B.at(i).first > B.at(i+1).first) Q.push({B.at(i).second,s,B.at(i).first});
        s += B.at(i).second;
    }
    while(Q.size()){
        auto [len,l,v] = Q.top(); Q.pop();
        if(S.count({l,len,v}) == false) continue;
        auto itr = S.lower_bound({l,len,v});
        itr++;
        int r = l+len-1;
        auto [l2,len2,v2] = *itr;
        itr--;itr--;
        auto [l1,len1,v1] = *itr;
        itr++;
        vector<tuple<int,int,int>> era = {*itr};

        long long now = 1LL*len*(v-max(v1,v2));
        if(K <= now){
            answer -= K/len*2;
            break;
        }
        else answer -= (v-max(v1,v2))*2,K -= now,v = max(v1,v2);
        if(v1 == v) l = l1,len += len1,era.push_back({l1,len1,v1});
        if(v2 == v) len += len2,era.push_back({l2,len2,v2});
        for(auto &e : era) S.erase(e);
        S.insert({l,len,v});
        if(v && A.at(l-1) < v && v > A.at(l+len)) Q.push({len,l,v});
    }
    cout << answer << endl;
}