#include <bits/stdc++.h>
using namespace std;
#define int long long
#define inf 0x3F3F3F3F3F3F3F3F
const int MXN = 5e5 + 5;
const int mod = 1e9 + 7;
array<int, 2> dp[MXN];
void _()
{
int n;
cin >> n;
int a[n + 1], p[n + 1];
for (int i = 1; i <= n; i++) cin >> a[i];
p[0] = 0;
for (int i = 1; i <= n; i++) p[i] = (i ? p[i - 1] : 0) + a[i];
auto sum = [&](int l, int r)
{
if (l > r) return 0LL;
return p[r] - (l ? p[l - 1] : 0LL);
};
dp[0] = {0, 0};
priority_queue<array<int, 3>, vector<array<int, 3>>, greater<array<int, 3>>> pq;
pq.push({0, 0});
array<int, 2> cur = {0, 0};
for (int i = 1; i <= n; i++)
{
while (!pq.empty() && pq.top()[0] <= p[i])
{
int j = pq.top()[1];
pq.pop();
if (dp[j][0] + 1 < cur[0]) continue;
if (dp[j][0] + 1 > cur[0]) cur = {dp[j][0] + 1, -p[j]};
else if (-p[j] <= cur[1]) cur[1] = -p[j];
}
dp[i] = {cur[0], cur[1] + p[i]};
pq.push({dp[i][1] + p[i], i});
}
cout << dp[n][0] << '\n';
}
signed main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
int t = 1;
// cin >> t;
while (t--) _();
}
