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#include <iostream>
#include <vector>
#include <unordered_set>
#include <algorithm>

using int64 = long long int;

int n;
std::vector<int> a;

int64 sum;

int p;
std::vector<int> tree;

void update_tree(int node, int left, int right, int update_left, int update_right, int count)
{
	if (update_left >= update_right)
		return;
	if (update_left == left && right == update_right)
	{
		tree[node] += count;
		return;
	}
	const int mid = (left + right) / 2;
	update_tree(node * 2, left, mid, update_left, std::min(update_right, mid), count);
	update_tree(node * 2 + 1, mid, right, std::max(update_left, mid), update_right, count);
}

struct entry
{
	int node, left, right, update_left, update_right;
};
entry stack[1 << 18];
int stack_size = 0;

void update_tree2(int node, int left, int right, int update_left, int update_right, int count)
{
	stack_size = 0;
	stack[stack_size++] = entry{ node, left, right, update_left, update_right };
	while (stack_size)
	{
		entry e = stack[(stack_size--) - 1];

		if (e.update_left == e.left && e.right == e.update_right)
		{
			tree[e.node] += count;
			continue;
		}

		const int mid = (e.left + e.right) / 2;
		{
			const int r = std::min(e.update_right, mid);
			if (e.update_left < r)
				stack[stack_size++] = entry{ e.node << 1, e.left, mid, e.update_left, r };
		}
		{
			const int l = std::max(mid, e.update_left);
			if (l < e.update_right)
				stack[stack_size++] = entry{ (e.node << 1) + 1, mid, e.right, l, e.update_right };
		}
	}
}

int get_count(int index)
{
	int count = 0;
	int l = p + index;
	while (l > 0)
	{
		count += tree[l];
		l /= 2;
	}
	return count;
}

bool check(int k)
{
	for (int i = 0; i < n - k + 1; ++i)
	{
		const int count = get_count(i);
		if (count > 0)
			update_tree2(1, 0, p, i, i + k, -count);
		else if (count < 0)
			return false;
	}
	for (int i = n - k + 1; i < n; ++i)
	{
		const int count = get_count(i);
		if (count != 0)
			return false;
	}
	return true;
}

bool check2(int k)
{
	std::vector<int> pop(n, 0);
	int sub = 0;
	for (int i = 0; i < n; ++i)
	{
		if (i > 0)
			sub -= pop[i - 1];
		if (a[i] > sub)
		{
			if (i + k - 1 >= n)
				return false;
			const int diff = a[i] - sub;
			sub += diff;
			pop[i + k - 1] += diff;
		}
		else if (a[i] < sub)
			return false;
	}
	return true;
}

int main()
{
#if 1
	std::cin >> n;
	a.resize(n);
	for (int i = 0; i < n; ++i)
	{
		std::cin >> a[i];
		sum += a[i];
	}
#else
	n = 100000;
	a.resize(n);
	for (int i = 0; i < n; ++i)
	{
		a[i] = i;
		sum += a[i];
	}
#endif

#if 0
	std::vector<int> reusable_tree;
	p = 1;
	while (p < n)
		p *= 2;
	reusable_tree.resize(p * 2, 0);
	for (int i = 0; i < n; ++i)
		reusable_tree[p + i] = a[i];
	for (int i = p - 1; i > 0; --i)
	{
		int& left = reusable_tree[i * 2];
		int& right = reusable_tree[i * 2 + 1];
		const int shared = std::min(left, right);
		left -= shared;
		right -= shared;
		reusable_tree[i] += shared;
	}
#endif

	int max_wave = 1;
	std::unordered_set<int> nope;
	for (int i = 2; i <= n; ++i)
	{
		if (sum % i == 0)
		{
			bool div_prev = false;
			for (int j : nope)
				if (i % j == 0)
				{
					div_prev = true;
					break;
				}
			if (div_prev)
				continue;

#if 0
			tree = reusable_tree;
			if (check(i))
			{
				max_wave = i;
				continue;
			}
#else
			if (check2(i))
			{
				max_wave = i;
				continue;
			}
#endif
			nope.insert(i);
		}
	}

	std::cout << max_wave << std::endl;
	return 0;
}

/*

5
1 1 0 1 1

5
1 0 0 1 1


8
1 2 3 4 5 5 3 1

4
1 1 0 0

*/