/***Farhan132***/
// #pragma GCC optimize("Ofast,fast-math")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,fma")
// #pragma GCC optimization ("unroll-loops")
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef double dd;
typedef pair<ll , ll> ii;
typedef tuple < ll, ll, ll > tp;
#define ff first
#define ss second
#define pb push_back
#define in insert
#define bug printf("**!\n")
#define mem(a , b) memset(a, b ,sizeof(a))
#define front_zero(n) __builtin_clz(n)
#define back_zero(n) __builtin_ctzll(n)
#define total_one(n) __builtin_popcount(n)
#define clean fflush(stdout)
const ll mod = (ll) 998244353;
// const ll mod = (ll) 1e9 + 7;
//const ll INF = numeric_limits<ll>::max()-1;
const ll INF = (ll)2e18;
// ll dx[]={0,1,0,-1};
// ll dy[]={1,0,-1,0};
// ll dxx[]={0,1,0,-1,1,1,-1,-1};
// ll dyy[]={1,0,-1,0,1,-1,1,-1};
mt19937 rng(chrono::system_clock::now().time_since_epoch().count());
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
template <typename T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
const ll N = 5e5 + 5;
ll f[N], pref[N], a[N], k[N], ans[N];
set < pair < ll , ll > > s[N];
void solve(){
pref[0] = 0;
ll n; cin >> n;
for(ll i = 1; i <= n; i++){
cin >> a[i];
pref[i] = pref[i - 1] + a[i];
f[i] = INF;
}
ll cur = 0;
ll last = 0;
f[0] = 0, k[0] = 0, ans[0] = 0;
s[0].in({0, 0});
ll to = 0;
for(ll i = 1; i <= n; i++){
// p_i + f_j >= 0
if(- (*s[cur].begin()).ff + pref[i] >= 0){
cur++;
to = (*s[cur-1].begin()).ss;
}
while(s[cur - 1].size() > 0){
auto it = s[cur - 1].begin(); s[cur - 1].erase(it);
to = max((*it).ss, to);
if(s[cur-1].size() == 0 || - (*s[cur - 1].begin()).ff + pref[i] < 0){
s[cur - 1] .in(*it);
break;
}
}
s[cur].in({pref[i] + (pref[i] - pref[to]), i});
}
cout << cur << '\n';
return;
}
int main() {
#ifdef LOCAL
freopen("in.txt", "r", stdin);
freopen("out.txt", "w", stdout);
auto start_time = clock();
#else
// freopen("subsequence.in", "r", stdin);
// freopen("subsequence.out", "w", stdout);
ios_base::sync_with_stdio(0); cin.tie(NULL); cout.tie(NULL);
#endif
//precalc();
ll T = 1, CT = 0;// cin >> T;
while(T--){
// cout << "Case #" << ++CT << ": ";
solve();
}
#ifdef LOCAL
auto end_time = clock();
cerr<< "Execution time: "<<(end_time - start_time)*(int)1e3/CLOCKS_PER_SEC<<" ms\n";
#endif
return 0;
}
