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#include <iostream>
#include <numeric>
#include <cstdint>


using namespace std;


struct Run
{
	int32_t m_iLeft;
	int32_t m_iRight;
	int64_t m_iSize;
	int64_t m_iLen;
	int64_t m_iSum;
};


static int32_t iTotalSize, iRunCnt;

static int64_t iAnswer, iGCD, iMinRunLen;

static int32_t a[100'004];

static int64_t d[100'004];

static Run aRuns[40'000];


static void ReadData()
{
	iAnswer = 1;

	cin >> iTotalSize;

	for (int32_t i = 0; i < iTotalSize; ++i)
	{
		cin >> a[i];
	}

	a[iTotalSize++] = 0;
}


static bool IsWaveLenOK(int iWaveLen, const Run & run)
{
	for (int32_t i = 0; i < run.m_iSize; ++i)
	{
		d[run.m_iLeft + i] = 0;
	}

	int64_t iCurrNumOfWaves = 0;
	int64_t iNumOfNewWaves = 0;

	for (int32_t i = 0;; ++i)
	{
		iCurrNumOfWaves += d[run.m_iLeft + i];

		if (i >= run.m_iSize - 1)
			return iCurrNumOfWaves == 0;

		iNumOfNewWaves = a[run.m_iLeft + i] - iCurrNumOfWaves;

		if (iNumOfNewWaves < 0) return false;

		if (iNumOfNewWaves == 0)
		{
			continue;
		}

		if (i + iWaveLen >= run.m_iSize) return false;

		d[run.m_iLeft + i + iWaveLen] = (-iNumOfNewWaves);

		iCurrNumOfWaves += iNumOfNewWaves;
	}
}


static bool IsWaveLenOK(int64_t iWaveLen)
{
	for (int32_t i = 0; i < iRunCnt; ++i)
	{
		if (!IsWaveLenOK((int) iWaveLen, aRuns[i]))
			return false;
	}

	return true;
}


static void Solve()
{
	for (int64_t iWaveLen = min(iMinRunLen, iGCD); iWaveLen > 1; --iWaveLen)
	{
		if ((iGCD % iWaveLen) != 0) continue;

		if (IsWaveLenOK(iWaveLen))
		{
			iAnswer = iWaveLen;
			break;
		}
	}
}


static bool PrepareRuns()
{
	bool fInRun = false;

	iRunCnt = 0;

	for (int32_t i = 0; i < iTotalSize; ++i)
	{
		Run & run = aRuns[iRunCnt];

		if (!fInRun)
		{
			if (a[i] == 0) continue;

			fInRun = true;

			run.m_iLeft = i;
			run.m_iSum = a[i];
			continue;
		}

		if (a[i] != 0)
		{
			run.m_iSum += a[i];
			continue;
		}

		fInRun = false;
		run.m_iRight = i - 1;
		run.m_iLen = i - run.m_iLeft;
		run.m_iSize = run.m_iLen + 1;

		if (run.m_iLen == 1)
			return false;

		if (iRunCnt++ == 0)
		{
			iGCD = run.m_iSum;
			iMinRunLen = run.m_iLen;
		}
		else
		{
			iGCD = gcd(iGCD, run.m_iSum);
			iMinRunLen = min(iMinRunLen, run.m_iLen);

			if (iGCD == 1) return false;
		}
	}

	return true;
}


int main()
{
	// freopen("sample_input.txt", "r", stdin);
	// freopen("sample_output.txt", "w", stdout);

	ReadData();

	if (PrepareRuns())
	{
		Solve();
	}

	cout << iAnswer;
}