#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pi pair<int, int>
#define vi vector<int>
vector<int> a;
vector<int> prfx;
/*
sum(j+1, i) >= a_j
sum(j+1, i) - a_j >= 0
sum(j+1, i) - a_j - sum(0, i) >= -sum(0, i)
-sum(0, j) - a_j >= -sum(0, i)
sum(0, j) + a_j <= sum(0, i)
2 + 2 <= 5
4 <= 5
*/
int getPrfx(int l, int r) {
int left = (l == 0) ? 0 : prfx[l - 1];
int right = prfx[r];
return right - left;
}
bool compare(pi a, pi b) {
if (a.first > b.first) return true;
if (a.first < b.first) return false;
if (a.second < b.second) return true;
return false;
}
pi findIndex(int i, vi& a, vector<pi>& dp, vector<pi> prv) {
int s1 = getPrfx(0, i);
int mn = INT32_MIN;
for (int k = 0; k < prv.size(); k++) {
if (prv[k].first > s1) continue;
mn = max(mn, prv[k].second);
}
if (mn == INT32_MIN) {
return {INT32_MIN, -1};
}
int j = mn;
int s2 = getPrfx(j+1, i);
pi c = {dp[j+1].first+1, s2};
return c;
}
signed main() {
int n;
cin >> n;
a.resize(n);
for (int i = 0; i < n; ++i) cin >> a[i];
prfx.resize(n);
prfx[0] = a[0];
for (int i = 1; i < n; ++i) {
prfx[i] = prfx[i - 1] + a[i];
}
vector<pi> dp(n+1, {INT32_MIN, INT64_MAX});
dp[0] = {1, 0};
int mx = 0;
vector<pi> prv;
vector<pi> prv2;
for (int i = 0; i < n; i++) {
int x = a[i];
pi res = dp[i];
res.second += x;
pi c1 = findIndex(i, a, dp, prv);
pi c2 = findIndex(i, a, dp, prv2);
if (compare(c1, res)) res = c1;
if (compare(c2, res)) res = c2;
dp[i+1] = res;
if (res.first > mx) {
mx = res.first;
swap(prv2, prv);
prv.clear();
}
int s1 = getPrfx(0, i);
prv.push_back({s1 + res.second, i});
/*
for (int j = 0; j < i; j++) {
pi c = dp[j+1];
//cerr << j+1 << ' ' << i << ' ' << getPrfx(j, i-1) << endl;
int s = getPrfx(j+1, i);
if (s < c.second) continue;
c.second = s;
c.first++;
if (compare(c, res)) res = c;
}
*/
}
cout << dp[n].first;
}
