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#include <cstdio>
#include <cmath>
#include <iostream>
#include <algorithm>
#include <queue>
#include <list>
#include <vector>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <set>
#include <bitset>
#include <stack>
#include <string>
#include <cstring>
#include <cassert>
#include <limits.h>
#include <numeric>

using namespace std;

typedef long long LL;
typedef long double LD;

typedef vector<int> VI;
#define REP(i,n) for(int i=0;i<(n);i++)
#define FOR(i,a,b) for(VAR(i,a);i<=(b);++i)
#define FORD(i,a,b) for(VAR(i,a);i>=(b);--i)
#define FORE(a,b) for(VAR(a,(b).begin());a!=(b).end();++a)
#define VAR(a,b) __typeof(b) a=(b)
#define SIZE(a) ((int)((a).size()))
#define ALL(x) (x).begin(),(x).end()
#define CLR(x,a) memset(x,a,sizeof(x))
#define ZERO(x) memset(x,0,sizeof(x))
#define S(t,i) scanf("%" ## t, &i)
#define SI(i) scanf("%d", &i)

const int MAXN=100000+1;
int n, k;
int a[MAXN];
int diff[2*MAXN];
int lp[MAXN];
int pr[MAXN];
int pr_count=0;
list<int> answers;
list<pair<int,int>> intervals;
LL gsum;
int minl=INT_MAX;


// void sieve(){
//     for (int i=2; i <= MAXN; ++i) {
//         if (lp[i] == 0) {
//             lp[i] = i;
//             pr[pr_count] = i;
//             pr_count++;
//         }
//         for (int j = 0; i * pr[j] <= MAXN; ++j) {
//             lp[i * pr[j]] = pr[j];
//             if (pr[j] == lp[i]) {
//                 break;
//             }
//         }
//     }
// }

bool check(int start, int end, int l) {
    //assert(l <= end-start+1);

    FOR(i, start, end) {
        diff[i]=0;
    }
    int tdiff=0;
    FOR(ai, start, end-l+1) {
        tdiff -= diff[ai];
        if (a[ai]-tdiff < 0) {
            return false;
        } else {
            diff[ai+l] = a[ai]-tdiff;
            tdiff = a[ai];
        }
    }
    FOR(ai, end-l+1+1, end) {
        tdiff -= diff[ai];
        if (a[ai] != tdiff) {
            return false;
        }
    }
    return true;
}

void solve1(int start, int end) {
    int m=min((LL)end-start+1, gsum);
    FOR(l, 2, m) {
        if (gsum % l == 0) {
            if (check(start, end, l)) {
                answers.push_back(l);
            }
        }
    }
}

void solve2(int start, int end) {
    for (auto ai=answers.begin(); ai != answers.end();) {
        if (!check(start, end, *ai)) {
            ai = answers.erase(ai);
        } else {
            ai++;
        }
    }
}

int ans=0;

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cin >> n;
    REP(ai, n) {
        cin >> a[ai];
    }
    //sieve();


    int ai=0;
    while (ai < n) {
        while (a[ai]==0 && ai < n) {
            ai++;
        }
        int start = ai;
        LL sum=0;
        while (a[ai] != 0 && ai < n) {
            sum += a[ai];
            ai++;
        }
        int end = ai-1;
        if (start <= end) {
            if (gsum == 0) {
                gsum = sum;
            } else {
                gsum = gcd(gsum, sum);
            }
            if (minl > end-start+1) {
                minl = end-start+1;
                intervals.push_front({start, end});
            } else {
                intervals.push_back({start, end});
            }
        }
    }
    solve1(intervals.front().first, intervals.front().second);
    intervals.pop_front();
    FORE(ii, intervals) {
        solve2(ii->first, ii->second);
    }

    if (!answers.empty()) {
        cout << answers.back() << "\n";
    } else {
        cout << "1\n";
    }
    return 0;
}