/**
	author:  shobonvip
	created: 2026.08.25 15:14:34
**/

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

//* ATCODER
#include<atcoder/all>
using namespace atcoder;
typedef modint998244353 mint;
//*/

/* BOOST MULTIPRECISION
#include<boost/multiprecision/cpp_int.hpp>
using namespace boost::multiprecision;
//*/

typedef long long ll;

#define rep(i, s, n) for (int i = (int)(s); i < (int)(n); i++)
#define rrep(i, s, n) for (int i = (int)(n)-1; i >= (int)(s); i--)
#define all(v) v.begin(), v.end()

template <typename T> bool chmin(T &a, const T &b) {
	if (a <= b) return false;
	a = b;
	return true;
}

template <typename T> bool chmax(T &a, const T &b) {
	if (a >= b) return false;
	a = b;
	return true;
}

template <typename T> T max(vector<T> &a){
	assert(!a.empty());
	T ret = a[0];
	for (int i=0; i<(int)a.size(); i++) chmax(ret, a[i]);
	return ret;
}

template <typename T> T min(vector<T> &a){
	assert(!a.empty());
	T ret = a[0];
	for (int i=0; i<(int)a.size(); i++) chmin(ret, a[i]);
	return ret;
}

template <typename T> T sum(vector<T> &a){
	T ret = 0;
	for (int i=0; i<(int)a.size(); i++) ret += a[i];
	return ret;
}

struct UnionFind{
	int n;
	vector<int> par;
	vector<int> l, r, v;

	explicit UnionFind(int t): n(t), par(t,-1), l(t), r(t), v(t) {
		iota(all(l), 0);
		iota(all(r), 0);
	}

	void merge(int a, int b){
		int x = find(a);
		int y = find(b);
		if (x == y) return;
		if (-par[x] < -par[y]) swap(x, y);
		chmin(l[x], l[y]);
		chmax(r[x], r[y]);
		v[x] = v[y];
		par[x] += par[y];
		par[y] = x;
		return;
	}

	int find(int x){
		if (par[x] < 0) return x;
		return par[x] = find(par[x]);
	}
};


int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	
	int n; ll k; cin >> n >> k;

	vector<ll> a(n+2);
	rep(i,1,n+1) {
		cin >> a[i];
	}

	UnionFind uf(n + 2);
	rep(i,0,n+2) {
		uf.v[i] = a[i];
	}

	rep(i,0,n+1) {
		if (a[i] == a[i+1]) {
			uf.merge(i, i+1);
		}
	}

	rep(len,1,n+1) {
		for (int l=1; l<=n; l+=len) {
			int g = uf.find(l);
			int lft = uf.l[g];
			int rgt = uf.r[g];
			//cout << l << ' ' << g << ' ' << lft << ' ' << rgt << ' ' << len << endl;
			if (lft + len - 1 == rgt) {
				if (lft - 1 >= 0 && rgt + 1 <= n+1) {
					if (uf.v[lft-1] < uf.v[g] && uf.v[g] > uf.v[rgt+1]) {
						ll t = max(uf.v[lft-1], uf.v[rgt+1]);
						int tar = min(k / len, uf.v[g] - t);
						uf.v[g] -= tar;
						k -= ll(tar) * len;

						if (uf.v[lft-1] == uf.v[g]) {
							uf.merge(lft-1, g);
							g = uf.find(l);
						}

						if (uf.v[rgt+1] == uf.v[g]) {
							uf.merge(rgt+1, g);
							g = uf.find(l);
						}
					}
				}
			}
		}
	}

	ll ans = 0;

	rep(i,0,n+1) {
		//cout << uf.v[uf.find(i)] << ' ';
		if (uf.find(i) != uf.find(i+1)) {
			ans += abs(uf.v[uf.find(i)] - uf.v[uf.find(i+1)]);
		}
	}

	cout << ans << endl;

}