#include <bits/stdc++.h>
#define ff first
#define ss second
typedef long long ll;
using namespace std;
const int N = 5e5 + 10;
const ll INF = 2e18 + 10;
ll pref[N];
pair <ll, ll> dp[N];
ll dpp[N];
ll tree[4 * N];
int n;
void upd(int v, int tl, int tr, int pos, ll val) {
if (tl == tr) {
tree[v] = val;
return;
}
int tm = (tl + tr) / 2;
if (pos <= tm) upd(2 * v, tl, tm, pos, val);
else upd(2 * v + 1, tm + 1, tr, pos, val);
tree[v] = min(tree[2 * v], tree[2 * v + 1]);
}
int get(ll p) {
int v = 1, tl = 1, tr = n + 1;
while (tl != tr) {
int tm = (tl + tr) / 2;
if (tree[2 * v + 1] <= p) {
v = 2 * v + 1;
tl = tm + 1;
}
else {
v = 2 * v;
tr = tm;
}
}
return tl;
}
int main() {
cin >> n;
for (int i = 1; i <= 4 * n + 4; i++) {
tree[i] = INF;
}
for (int i = 1; i <= n; i++) {
cin >> pref[i];
pref[i] += pref[i - 1];
}
dp[0] = { 0, 0 };
dpp[0] = 0;
upd(1, 1, n + 1, 0 + 1, dpp[0]);
for (int i = 1; i <= n; i++) {
int ind = get(pref[i]) - 1;
dp[i] = { dp[ind].first + 1, pref[i] - pref[ind] };
dpp[i] = dp[i].ss + pref[i];
upd(1, 1, n + 1, i + 1, dpp[i]);
}
cout << dp[n].ff << "\n";
}
