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// Marcin Knapik

// Potyczki Algorytmiczne 2020 - runda druga zadanie B

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

#define f first
#define s second
#define sz(s) (int)s.size()
#define all(s) s.begin(), s.end()
#define pb push_back
#define vi vector<int>

#define ld long long
#define ll long long
#define ii pair<int, int>
#define vi vector<int>
#define vii vector<ii>
#define vvi vector<vi>

const ll INF = 1e18;
const int inf = 1e9;

int main(){
    ios::sync_with_stdio(0);
    cin.tie(0);

    int n;    cin >> n;
    vi tab(n);
    int ostatnia_ujemna = -1;
    for(int i = 0; i < n; i++){
        cin >> tab[i];
        if(tab[i] < 0)
            ostatnia_ujemna = i;
    }

    if(ostatnia_ujemna == -1){
        cout << 0 << '\n';
        exit(0);
    }

    set<pair<ll, int> > secik = { {-INF, inf}, {0ll, 0ll} };

    ll suma = 0;
    int ile = 0;
    int ans = n - 1;
    int best_do_tej_pory = 0;

    for(int i = 0; i < n; i++){
        ile++;
        suma += tab[i];

        if(tab[i] < 0)
            best_do_tej_pory = inf;

        auto it = secik.upper_bound({suma, inf});
        assert(it != secik.begin());
        it = prev(it);

        if(it == secik.begin())
            continue;

        best_do_tej_pory = min(best_do_tej_pory, (*it).s + ile - 1);
        if(i >= ostatnia_ujemna)
            ans = min(ans, best_do_tej_pory);

        while(it != prev(secik.end()) and (*next(it)).s >= best_do_tej_pory - ile)
            secik.erase(next(it));

        if(best_do_tej_pory - ile < (*it).s){
            if((*it).f == suma)
                secik.erase(it);
            secik.insert({suma, best_do_tej_pory - ile});
        }
    }

    cout << ans << '\n';
}