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#include <cstdio>
#include <vector>
#include <cmath>

#ifdef LOCAL
    #define dbg(...) fprintf(stderr, __VA_ARGS__)
#else
    #define dbg(...)
#endif

using namespace std;

constexpr long long MAX_SQRT = 320000; // max prime we can find when factorizing

bool is_prime(const long long n, const vector<long long>& lower_primes) {
    const long long sqrt1 = sqrt(n);
    // start with j=2 because we only check 6n-1, 6n+1, which are never divisible by 2 and 3
    for (unsigned long j = 2; j < lower_primes.size(); ++j) {
        if (lower_primes[j] > sqrt1) {
            break;
        }
        if (n % lower_primes[j] == 0) {
            return false;
        }
    }
    return true;
}

vector<long long> compute_primes(const long long max_n) {
    vector<long long> primes;
    primes.push_back(2);
    primes.push_back(3);

    for (int i = 6; i <= max_n; i += 6) {
        long long candidate_1 = i - 1;
        if (is_prime(candidate_1, primes)) {
            primes.push_back(candidate_1);
        }

        long long candidate_2 = i + 1;
        if (is_prime(candidate_2, primes)) {
            primes.push_back(candidate_2);
        }
    }

    return primes;
}

vector<long long> factorize(long long n, vector<long long>& primes) {
    dbg("Factorizing %lld\n", n);
    vector<long long> fact;

    for (const long long prime: primes) {
        while (n % prime == 0) {
            fact.push_back(prime);
            n /= prime;
        }
        if (n == 1) break;
    }
    if (n != 1) fact.push_back(n);
    dbg("Found %lu prime factors\n", fact.size());
    return fact;
}

bool solution_possible(const long long k, const vector<long long>& plarza) {
    vector<long long> wavesizes;
    long long totalwaves = 0;
    const unsigned long plen = plarza.size();
    for (unsigned long i = 0; i < plen; ++i) {
        if (static_cast<long long>(i) >= k) {
            // end old wave if we're far enough
            dbg("wave of size %lld started at %lld has no effect now\n", (wavesizes[i-k]), i-k);
            totalwaves -= wavesizes[i-k];
        }
        dbg("current value is %lld, and guaranteed waves total to %lld\n", plarza[i], totalwaves);
        if (plarza[i] < totalwaves) {
            dbg("FAIL: guaranteed waves are too high\n");
            return false;
        }
        if (i + k <= plen) {
            // start a new wave if we can fit it
            dbg("starting wave of size %lld at position %lu\n", (plarza[i] - totalwaves), i);
            wavesizes.push_back(plarza[i] - totalwaves);
            totalwaves += (plarza[i] - totalwaves);
        } else {
            // if we can't start a new wave, completion must be exact
            if (plarza[i] != totalwaves) {
                dbg("FAIL: stuff still remaining, but can't start a new wave\n");
                return false;
            }
        }
    }
    return true;
}

int main() {
    int n;
    vector<long long> plarza;
    long long totalsum = 0LL;
    long long max_a = 0LL; // minimum number of waves
    long long first_desc = -1;
    long long last_asc = 0;

    vector<long long> primes = compute_primes(MAX_SQRT);
    scanf("%d", &n);
    long long prevy = -1;
    for (int i = 0; i < n; ++i) {
        long long y;
        scanf("%lld", &y);
        plarza.push_back(y);
        if (y > prevy) last_asc = i;
        if (first_desc == -1 && y < prevy) first_desc = i;
        if (y > max_a) {
            max_a = y;
        }
        totalsum += y;
        prevy = y;
    }

    if (first_desc == -1 && last_asc == 0) {
        // constant val
        printf("%d\n", n);
        return 0;
    }

    // this can be -1 if sequence is non-desc / non-asc, but not constant.
    // we will just return "1" then
    long long max_size = min(first_desc, (n - last_asc));


    vector<long long> sum_factors = factorize(totalsum, primes);
    dbg("Max wave size due to ascending/descending values is %lld\n", max_size);
    dbg("Total sum is: %lld\n", totalsum);
    dbg("Factors of total sum:\n");
    for (auto& factor: sum_factors) {
        dbg("%lld ", factor);
    }
    dbg("\n");

    for (long long i = max_size; i >= 2; --i) {
        if (totalsum % i != 0) continue;
        dbg("--- Checking possibility of %lld solution...\n", i);
        if (solution_possible(i, plarza)) {
            printf("%lld\n", i);
            return 0;
        }
    }
    printf("1\n");
    return 0;
}