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

void solve();
signed main(){
    ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
    solve();
}

void solve(){
    int n;
    cin>>n;
    vector<ll>a(n+5,0),dp(n+5,0),s(n+5,0);
    for(int i=1;i<=n;i++)cin>>a[i],s[i]=s[i-1]+a[i];
    for(int i=1;i<=n;i++){
        dp[i]=s[i];
        int l=0;
        for(int r=i,m;l+1<r;){
            m=(l+r)/2;
            if(dp[m]+s[m]<=s[i])l=m;
            else r=m;
        }
        dp[i]=s[i]-s[l];
    }
    ll mn=dp[n];
    for(int j=n;j>=0;j--){
        mn=min<ll>(mn,max<ll>(s[n]-s[j],dp[j]));
    }
    cout<<mn<<"\n";
}