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#include "bits/stdc++.h"
using namespace std;
using ll = long long;

int const N = 1e5+5;
int n, a[N], b[N];
ll sum;

int main(){
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    cin >> n;
    for(int i = 0; i < n; ++i) cin >> a[i], sum += a[i];
    auto check = [&](int x) -> bool{
        //cout << x << '\n';
        for(int i = 0; i < n; ++i) b[i] = 0;
        ll curr = 0;
        for(int i = 0; i < n; ++i){
            if(i >= x) curr -= b[i-x];
            if(a[i]-curr < 0) return false;
            if(a[i]-curr != 0 && i+x > n) return false;
            b[i] = a[i]-curr;
            curr += a[i]-curr;
        }
        return true;
    };
    for(int k = n; k; --k){
        if(sum%k) continue;
        if(check(k)){
            cout << k << '\n';
            return 0;
        }
    }
}