Envío 5215

Código

/// Write by Daniel Perez .PERAPRO
#include<bits/stdc++.h>

using namespace std;
#define fast_io ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define pb push_back
#define ff first
#define ss second
#define all(s) s.begin(), s.end()
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
using vi=vector<int>;
using vl=vector<ll>;
using pii=pair<int,int>;
char el = '\n';
char esp = ' ';

template<class T> bool ckmin(T& a, const T& b) { return b < a ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; }

ostream& operator<<(ostream& os, const vector<int> &v){
    for(auto const &i: v){
        os<<i<<" ";
    }
    os<<'\n';
    return os;
}
string yes="YES";
string no="NO";

int main(){
	fast_io;
	/*
 	freopen("input.txt","r",stdin);
    freopen("output.txt","w",stdout);
    */
    int n;
    cin>>n;
    vl v(n);
    
    for(int i=0;i<n;i++){
        cin>>v[i];
        v[i] = -v[i];
    }
    
    vl right(n);
    vl left(n);
    
    stack<ll> st;
    
    right[n - 1] = n - 1;
    st.push(n - 1);
    
    for(int i =n - 2;i >=0;i--){
        //int cur = st.top();
        while(st.size() && v[i] >= v[st.top()]){
            st.pop();
            //cur = st.top();
        }
        right[i] = (st.size() ? st.top() - 1 : n - 1);
        st.push(i);
    }
    
    while(st.size()) st.pop();
    
    left[0] = 0;
    st.push(0);
    
    for(int i =1;i<n;i++){
        while(st.size() && v[i] >= v[st.top()]){
            st.pop();
        }
        left[i] = (st.size() ? st.top() + 1: 0);
        st.push(i);
    }
    
    ll ans = 0;
    //cout<<left<<right;
    for(int i=0;i<n;i++){
        ckmax(ans, -v[i] * ( (i - left[i] + 1) + (right[i] - i) ));
    }
    
    cout<<ans<<el;
}

/*

*/