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#include<bits/stdc++.h>
using namespace std;
#define ll long long

vector<ll> nums;
ll n;

bool is_possible(ll k){
    ll i;
    vector<ll> s(n);
    s[0] = nums[0];
    for(i=1; i<n; ++i){
        s[i] = nums[i]-nums[i-1];
        if(i>=k) s[i]+=s[i-k];
        if(s[i]<0) return false;
        if(i>n-k && s[i]>0) return false;
    }
    return true;
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    cin >> n;
    ll i, sum=0;
    nums.resize(n);
    for(i=0; i<n; ++i){ cin >> nums[i]; sum+=nums[i];}
    ll L, R;
    for(L=1; L<n; ++L) if(nums[L]<nums[L-1]) break;
    for(R=n-2; R>=0; R--) if(nums[R]<nums[R+1]) break;
    
    for(i=min(L, n-R-1); i>=1; i--){
        if(sum%i!=0) continue;
        if(is_possible(i)){ cout << i; return 0;}
    }
    cout << 1;
}