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#include <bits/stdc++.h>

using namespace std;

typedef unsigned uint;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ldbl;
typedef pair<int, int> pii;
typedef pair<uint, uint> puu;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> pull;
typedef pair<double, double> pdd;
typedef vector<int> vi;
typedef vector<uint> vu;
typedef vector<ll> vll;
typedef vector<ull> vull;
typedef vector<pii> vpii;
typedef vector<puu> vpuu;
typedef vector<pll> vpll;
typedef vector<pull> vpull;
typedef vector<string> vstr;
typedef vector<double> vdbl;
typedef vector<ldbl> vldbl;
#define pb push_back
#define ppb pop_back
#define pfr push_front
#define ppfr pop_front
#define emp emplace
#define empb emplace_back
#define be begin
#define rbe rbegin
#define all(x) (x).be(), (x).end()
#define rall(x) (x).rbe(), (x).rend()
#define fir first
#define sec second
#define mkp make_pair
#define brif(cond) if (cond) break
#define ctif(cond) if (cond) continue
#define retif(cond) if (cond) return
void fastio() {ios_base::sync_with_stdio(false);cin.tie(nullptr);}
template<typename T> T gcd(T a, T b) {return b ? gcd(b, a%b) : a;}
template<typename T> T extgcd(T a, T b, T &x, T &y)
{
    T x0 = 1, y0 = 0, x1 = 0, y1 = 1;
    while (b) {
        T q = a/b; a %= b; swap(a, b);
        x0 -= q*x1; swap(x0, x1);
        y0 -= q*y1; swap(y0, y1);
    }
    x = x0; y = y0; return a;
}
int ctz(uint x) {return __builtin_ctz(x);}
int ctzll(ull x) {return __builtin_ctzll(x);}
int clz(uint x) {return __builtin_clz(x);}
int clzll(ull x) {return __builtin_clzll(x);}
int popcnt(uint x) {return __builtin_popcount(x);}
int popcntll(ull x) {return __builtin_popcountll(x);}
int bsr(uint x) {return 31^clz(x);}
int bsrll(ull x) {return 63^clzll(x);}

#define N 100016

vpii seg;
int a[N], d[N];

bool check(int n, int k)
{
    copy_n(a, n+1, d);

    for (pii p : seg) {
        int l = p.fir, r = p.sec;
        for (int i = l; i <= r-k; ++i) {
            retif(d[i] < 0) false;
            if (d[i] > 0) d[i+k] += d[i];
        }
        for (int i = r-k+1; i <= r; ++i) {
            retif(d[i]) false;
        }
    }
    return true;
}

int main()
{
    fastio();

    int n, ub;
    ll m = 0;

    cin >> n;
    for (int i = 0; i < n; ++i) cin >> a[i];
    ub = n;
    for (int i = 0, j = 1; i < n; i = j++) {
        ctif(a[i] == 0);
        ll s = a[i];
        while (j < n && a[j] > 0) s += a[j++];
        seg.empb(i, j);
        ub = min(ub, j-i);
        m = gcd(s, m);
    }
    for (int i = n; i > 0; --i) a[i] -= a[i-1];
    for (int k = ub; k > 1; --k) {
        ctif(m%k);
        retif(check(n, k)) cout << k << '\n', 0;
    }
    cout << "1\n";

    return 0;
}