#include <bits/stdc++.h>
#define pb push_back
#define pf push_front
#define ppb pop_back
#define ppf pop_front
#define fi first
#define se second
#define mid ((x + y) / 2)
#define left (ind * 2)
#define right (ind * 2 + 1)
#define mp make_pair
#define timer ((double)clock() / CLOCKS_PER_SEC)
#define endl "\n"
#define spc " "
#define d1(x) cerr<<#x<<":"<<x<<endl
#define d2(x, y) cerr<<#x<<":"<<x<<" "<<#y<<":"<<y<<endl
#define d3(x, y, z) cerr<<#x<<":"<<x<<" "<<#y<<":"<<y<<" "<<#z<<":"<<z<<endl
#define fast_io() ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0)
using namespace std;
typedef long long int lli;
typedef pair<int, int> ii;
typedef pair<ii, int> iii;
typedef pair<double, double> dd;
const int N = (int)(1e6 + 5);
const int LOG = (int)(20);
int n, ans, ar[N];
deque<int> dq;
int main() {
fast_io();
// freopen("inp.in", "r", stdin);
cin >> n;
for(int i = 1; i <= n; i++) {
cin >> ar[i];
dq.pb(ar[i]);
}
while(!dq.empty()) {
int b = dq.back(), f = dq.front();
if(dq.size() == 1)
break;
if(b == f) {
dq.ppf();
dq.ppb();
continue;
}
if(f < b) {
dq.ppf();
int t = dq.front();
dq.ppf();
dq.pf(t + f);
ans++;
continue;
}
if(f > b) {
dq.ppb();
int t = dq.back();
dq.ppb();
dq.pb(t + b);
ans++;
continue;
}
}
cout << ans;
}
