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#include <iostream>
#include <vector>

typedef std::vector<uint32_t> bur_vect;

struct bur {
	uint32_t n;
	uint64_t sum;
	uint32_t max;
	uint64_t maxId;
	bur_vect v;
};

void print_bur(bur &b, bool print=false) {
	if (!print) {
		return;
	}
	std::cerr << "bur:{\n";
	std::cerr << "\tn:" << b.n << "\n";
	std::cerr << "\tsum:" << b.sum << "\n";
	std::cerr << "\tmax:" << b.max << "\n";
	std::cerr << "\tv: {";
	if (b.v.size() >= 1) {
		std::cerr << b.v[0];
	}
	for (uint32_t i = 1; i < b.v.size(); ++i) {
		std::cerr << ", " << b.v[i];
	}
	std::cerr << "}\n}\n";
}

bool check_light_bur(bur &b, uint32_t k, bool print=false) {
	if (k > b.n) {
		if (print) {
			std::cerr << "k>=b.n\n";
		}
		return false;
	}
	if (b.sum % k != 0) {
		if (print) {
			std::cerr << "b.sum%k !=0\n";
		}
		return false;
	}
	if (b.max * k > b.sum) {
		if (print) {
			std::cerr << "b.sum/k <=b.max\n";
		}
		return false;
	}
	uint32_t prev = b.v[0];
	for(uint32_t i = 1; i < k; ++i) {
		if (b.v[i] < prev) {
			if (print) {
				std::cerr << "niemalejacy\n";
			}
			return false;
		}
		prev = b.v[i];
	}
	
	uint32_t prev2 = b.v[b.v.size()-k];
	for(int32_t i = b.v.size() - k + 1; i < b.v.size(); ++i) {
		if (b.v[i] > prev2) {
			if (print) {
				std::cerr << "nierosnacy" << b.v[i] << " i:" << i << " n:" << prev2 << "\n";
			}
			return false;
		}
		prev2 = b.v[i];
	}
	return true;
}

void update_bur(bur &b) {
	uint64_t sum = 0;
	uint32_t max = 0;
	for(uint32_t i = 0; i < b.v.size(); ++i) {
		sum += b.v[i];
		if (b.v[i] > max) {
			max = b.v[i];
			b.maxId = i;
		}
	}
	b.sum = sum;
	b.max = max;
	b.n = b.v.size();
}

void relax_bur(bur &b, uint32_t k) {
	uint64_t newsum = b.sum;
	if (b.v.size() < k) {
		return;
	}
	int32_t start = b.v.size()-1;
	int32_t end = b.v.size() - k;
	uint32_t diff = b.v[start];
	for(int32_t i = start; i >= end; --i) {
		b.v[i] -= diff;
		newsum -= diff;
	}
	while (!b.v.empty() && b.v.back() == 0) {
		b.v.pop_back();
	}
	b.n = b.v.size();
	b.sum = newsum;
	return;
}

bool check_bur(bur &b, uint32_t k) {
	bur cb = b;
	while(true) {
		relax_bur(cb, k);
		if(cb.maxId < k || cb.maxId >= cb.v.size()-k){
			update_bur(cb);
		}
		if (cb.v.size() == 0 && cb.n == 0) {
			return true;
		}
		if (!check_light_bur(cb, k)) {
			//std::cerr << "Failed for k: in state:" << k << "\n";
			print_bur(cb);
			return false;
		}
		print_bur(cb);
	}
	return true;
}


void prog_main(std::istream& in, std::ostream& out)
{
	uint32_t n;
	in >> n;
	bur b {n, 0, 0, 0, bur_vect(n,0)};
	bool thesame = true;
	for (uint32_t i = 0; i < b.n; ++i) {
		in >> b.v[i];
		if (i > 0 && thesame) {
			if (b.v[i-1]!=b.v[i]) {
				thesame = false;
			}
		}
		b.sum += b.v[i];
		if (b.v[i] > b.max) {
			b.max = b.v[i];
			b.maxId = i;
		}
	}
	if (thesame) {
		out << b.n;
		return;
	}
	for(uint32_t i = b.n; i > 1; --i) {
		if (! check_light_bur(b, i)) {
			continue;
		}
		if (check_bur(b, i)) {
			out << i;
			return;
		}
	}
	out << 1;
}

#ifndef TEST
int main(int argc, char* argv[])
{
	prog_main(std::cin, std::cout);
	return 0;
}
#endif