#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using ll = long long;

using S = pair<ll,int>;
constexpr S e(){return make_pair(1ll << 60, 0);}
constexpr S op(S lhs, S rhs){return min(lhs, rhs);}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
    int n, m, v2;
    cin >> n >> m;
    vector<S> tmp(m);
    for(int i = 0; i < m; i++) tmp[i].second = i;
    atcoder::segtree<S, op, e> seg(tmp);
    for(int i = 0; i < n; i++){
        cin >> v2;
        auto [v, idx] = seg.all_prod();
        seg.set(idx, make_pair(v + v2, idx));
    }
    ll ans = 0;
    for(int i = 0; i < m; i++) ans = max(ans, seg.get(i).first);
    cout << ans << '\n';
}