#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pb push_back
#define ew "\n"
#define all(x) (x).begin(), (x).end()
#define st first
#define nd second
#define len(x) (int)x.size()
#define eb emplace_back
#define turbo \
ios_base::sync_with_stdio(false); \
cin.tie(0); \
cout.tie(0);
const int maxn = 1e6 + 12;
const int mxx = 100100;
const int MOD = 1e9 + 7;
const int inf = 2e18 + 7;
const int HH = 1e2 + 70;
int n;
int a[maxn], pref[maxn], t[maxn * 4], dp[maxn];
void upd(int v, int tl, int tr, int pos, int x)
{
if (tl == tr)
{
t[v] = x;
return;
}
int md = (tl + tr) >> 1;
if (pos <= md)
{
upd(v + v, tl, md, pos, x);
}
else
{
upd(v + v + 1, md + 1, tr, pos, x);
}
t[v] = min(t[v + v + 1], t[v + v]);
}
int get(int v, int tl, int tr, int x)
{
if (tl == tr)
{
return tl;
}
int md = (tl + tr) >> 1;
if (t[v + v + 1] <= x)
{
return get(v + v + 1, md + 1, tr, x);
}
else
{
return get(v + v, tl, md, x);
}
}
void code()
{
cin >> n;
for (int i = 0; i <= 4 * n; i++)
{
t[i] = inf;
}
for (int i = 1; i <= n; i++)
{
cin >> a[i];
pref[i] = pref[i - 1] + a[i];
}
for (int i = 1; i <= n; i++)
{
int j = 0;
if (t[1] <= pref[i])
{
j = get(1, 1, n, pref[i]);
}
dp[i] = dp[j] + 1;
upd(1, 1, n, i, pref[i] + (pref[i] - pref[j]));
}
cout << dp[n];
}
int32_t main()
{
// freopen("248.in", "r", stdin);
// freopen("248.out", "w", stdout);
// turbo;
int tt = 1, j = 1;
// cin >> tt;
while (tt--)
{
// cout << "Case " << j << ":" << ew;
code();
// j++;
}
}
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