#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<ll, ll>
#define fi first
#define sec second
#define ld long double
const int MAXN = 1e6;
const ll INF = 4e18;
const int MOD = 998244353;
int main(){
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
int tc = 1;
// cin >> tc;
for(;tc--;){
ll N; cin >> N;
vector<ll> a(N + 5), ps(N + 5);
for(int i = 1; i <= N; i++){
cin >> a[i];
ps[i] = ps[i - 1] + a[i];
}
vector<pii> dp(N + 5);
for(int i = 1; i <= N; i++) dp[i] = {-1, ps[i]};
for(int i = 1; i <= N; i++){
ll lf = i + 1, rg = N, ans = -1;
for(;lf <= rg;){
ll mid = (lf + rg) / 2;
if(ps[mid] - ps[i] >= dp[i].sec){
ans = mid;
rg = mid - 1;
}
else lf = mid + 1;
}
if(ans != -1){
for(int j = ans; j <= N; j++){
pii cur = {dp[i].fi - 1, ps[j] - ps[i]};
dp[j] = min(dp[j], cur);
}
}
}
cout << -dp[N].fi << "\n";
}
}
/*
1 2 3 4 5 6 7
*/
