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#include <stdio.h>


typedef  unsigned long long int  lli;


struct Number // == a * 10^b + c
{
	lli  a;   // number of digits in c is not greater than b
	int  b;
	int  c;

	void Init(int n)
	{
		a = n;
		b = 0;
		c = 0;
	}
};


static const int POWERS_CNT = 20;


static lli iTotal, iLen;

static lli aPowers[POWERS_CNT];

static int aIn[200002];


static void ReadData()
{
	scanf("%d", &iLen);

	for (int i = 0; i < iLen; ++i)
	{
		scanf("%d", aIn + i);
	}
}


static void InitPowers()
{
	aPowers[0] = 1;

	for (int i = 1; i < POWERS_CNT; ++i)
	{
		aPowers[i] = aPowers[i - 1] * 10;
	}
}


static inline int CountDigits(lli i)
{
	int iCnt = 0;

	while (i != 0)
	{
		i /= 10;
		iCnt++;
	}

	return iCnt;
}


static inline int CountDigits(const Number & n)
{
	return CountDigits(n.a) + n.b;
}


static inline int GetDigit(lli iNum, int iDigit)
{
	if (iDigit >= POWERS_CNT)
		return 0;

	return (iNum / aPowers[iDigit]) % 10;
}


static inline int GetDigit(const Number & n, int iDigit)
{
	if (iDigit >= n.b)
	{
		return GetDigit(n.a, iDigit - n.b);
	}

	return GetDigit(n.c, iDigit);
}


static inline int Compare(Number nX, lli iY)
{
	int iDigitsX = CountDigits(nX);
	int iDigitsY = CountDigits(iY);

	int iRet = iDigitsX - iDigitsY;

	if (iRet != 0)
		return iRet;

	for (int i = iDigitsY - 1; i >= 0; --i)
	{
		iRet = GetDigit(nX, i) - GetDigit(iY, i);

		if (iRet != 0)
			return iRet;
	}

	return 0;
}


// called when we know that x.c == 0 AND both arguments have the same number of digits

static inline int IsGreater_01(Number x, Number y, int iTotalDigits, int iDigitsXA) 
{
	for (int i = iTotalDigits - 1; iDigitsXA-- > 0; --i)
	{
		int iCmp = GetDigit(x, i) - GetDigit(y, i);

		if (iCmp > 0)
			return 1;

		if (iCmp < 0)
			return -1;
	}

	return 0;
}


static Number MakeStep(Number nPrev, lli iNext)
{
	Number nRet;

	nRet.Init(iNext);

	int iCmp = Compare(nPrev, iNext);

	if (iCmp < 0)
	{
		return nRet;
	}

	if (iCmp == 0)
	{
		iTotal++;
		nRet.b++;
		return nRet;
	}

	int iDigitsPrev = CountDigits(nPrev);  // this has just been counted inside Compare(); to be optimized
	int iDigitsNext = CountDigits(iNext);

	int iDigitCntDiff = iDigitsPrev - iDigitsNext;

	if (iDigitCntDiff == 0)
	{
		iTotal++;
		nRet.b++;
		return nRet;
	}

	Number nNextWithZeros = nRet;

	nNextWithZeros.b += iDigitCntDiff;

	iTotal += iDigitCntDiff;

	iCmp = IsGreater_01(nNextWithZeros, nPrev, iDigitsPrev, iDigitsNext);

	if (iCmp > 0)
	{
		return nNextWithZeros;
	}

	if (iCmp < 0)
	{
		iTotal++;
		nNextWithZeros.b++;
		return nNextWithZeros;
	}

	Number nNext2Ret = nNextWithZeros;

	if (nNextWithZeros.b > nPrev.b)
	{
		lli x = nPrev.a % aPowers[nNextWithZeros.b - nPrev.b];

		nNext2Ret.c = x;
	}
	else
		nNext2Ret.c = nPrev.c;

	nNext2Ret.c++;

	if (CountDigits(nNext2Ret.c) <= nNext2Ret.b)
	{
		return nNext2Ret;
	}

	iTotal++;
	nNextWithZeros.b++;
	return nNextWithZeros;
}


static void Solve()
{
	Number nPrev;

	nPrev.Init(aIn[0]);

	for (int i = 1; i < iLen; ++i)
	{
		Number nNewPrev = MakeStep(nPrev, aIn[i]);

		nPrev = nNewPrev;
	}
}


int main(int argc, char * argv[])
{
	ReadData();

	InitPowers();

	iTotal = 0;

	Solve();

	printf("%lld", iTotal);

	return 0;
}