1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <cassert>
using namespace std;
typedef unsigned long long ull;

string SillyAdd(string longerNumber, string shorterNumber)
{
	if (longerNumber.size() < shorterNumber.size())
		swap(longerNumber, shorterNumber);

	reverse(longerNumber.begin(), longerNumber.end());
	reverse(shorterNumber.begin(), shorterNumber.end());

	vector<int> resultantDigits;

	for (int i = 0; i < longerNumber.size(); ++i)
	{
		if (i >= shorterNumber.size())
			resultantDigits.push_back(longerNumber[i] - '0');
		else
		{
			resultantDigits.push_back(longerNumber[i] + shorterNumber[i] - 2 * '0');
		}
	}

	reverse(resultantDigits.begin(), resultantDigits.end());
	string result;
	for (int i = 0; i < resultantDigits.size(); ++i)
		result += to_string(resultantDigits[i]);

	return result;
}

class SimpleSolver
{
public:
	ull Solve(const ull number)
	{
		ull result = 0;
		string stringNumber = to_string(number);
		for (ull a = 0; a <= number; ++a)
		{
			string aString = to_string(a);
			for (ull b = 0; b <= number; ++b)
			{
				string bString = to_string(b);
				if (stringNumber == SillyAdd(aString, bString))
					++result;
			}
		}

		return result;
	}
};

class AdvacedSolver
{
public:
	ull Solve(const ull number)
	{
		return Solve(to_string(number));
	}
private:
	ull Solve(const string& number)
	{
		if (number.size() == 0)
			return 0;

		if (number[0] == '0' && number.size() > 1)
			return Solve(Trim0(number));

		if (number.size() == 1)
			return ComputeForNumberOfLength1(number);

		if (number.size() == 2)
			return ComputeForNumberOfLength2(number);

		const ull a = ComputeForNumberOfLength1(number.substr(0, 1)) * Solve(number.substr(1));
		const ull b = ComputeForNumberOfLength2WithSumGreaterThen9(number.substr(0, 2)) * Solve(number.substr(2));
		return a + b;
	}

	ull ComputeForNumberOfLength2(const string& stringNumber)
	{
		if (stringNumber[0] == '0')
			return ComputeForNumberOfLength1(stringNumber.substr(1));
		ull number = (stringNumber[0] - '0') * 10 + stringNumber[1] - '0';
		const ull result = (stringNumber[0] - '0' + 1) * (stringNumber[1] - '0' + 1);
		
		if (number > 19)
			return result;

		return result + 19 - number;
	}

	ull ComputeForNumberOfLength2WithSumGreaterThen9(const string& stringNumber)
	{
		ull number = (stringNumber[0] - '0') * 10 + stringNumber[1] - '0';

		if (number >= 19)
			return 0;

		return 19 - number;
	}

	ull ComputeForNumberOfLength1(const string& number)
	{
		return number[0] - '0' + 1;
	}

	string Trim0(const string& input)
	{
		int pos = 0;
		while (pos < input.size() && input[pos] == '0')
			++pos;

		return pos == input.size() ? "0" : input.substr(pos);
	}

};

//#define DEBUG

int main()
{
	SimpleSolver simpleSolver;
	AdvacedSolver advancedSolver;

#ifdef DEBUG
	assert(simpleSolver.Solve(112) == 50);
	for (int i = 0; i <= 9; ++i)
		assert(simpleSolver.Solve(i) == i + 1);

	assert(simpleSolver.Solve(12) == 13);
	assert(simpleSolver.Solve(11) == 12);
	assert(simpleSolver.Solve(21) == 6);
	assert(simpleSolver.Solve(100) == 11);
	assert(simpleSolver.Solve(1010) == 121);
	
	cout << simpleSolver.Solve(11) << endl;
	cout << simpleSolver.Solve(112) << endl;
	cout << simpleSolver.Solve(21) << endl;
	cout << "---\n";

	for (int i = 0; i <= 9; ++i)
		assert(advancedSolver.Solve(i) == i + 1);

	assert(advancedSolver.Solve(12) == 13);
	assert(advancedSolver.Solve(11) == 12);
	assert(advancedSolver.Solve(21) == 6);
	assert(advancedSolver.Solve(100) == 11);
	assert(advancedSolver.Solve(1000) == 11);
	cout << advancedSolver.Solve(112) << endl;

	for (int i = 1000; i < 1200; ++i)
	{
		ull ss = simpleSolver.Solve(i);
		ull as = advancedSolver.Solve(i);

		if (ss != as)
			cout << "Uups! (i=" << i << ") " << ss << " != " << as << endl;
	}
	cout << "Done!" << endl;

	cout << advancedSolver.Solve(1822187) << endl;
	cout << advancedSolver.Solve(1111111111) << endl;
	cout << advancedSolver.Solve(11111111111111111) << endl;
#endif
	ull number;
	cin >> number;

	cout << advancedSolver.Solve(number) << endl;

#ifdef DEBUG
	system("pause");
#endif
}