// The most evil program EVER.

#include <iostream>
#include <conio.h>

using namespace std;

typedef struct ul_conv {
	unsigned long msb;
	unsigned long lsb;
} ul_t;

typedef union decomposer_u {
	ul_t ul;
	unsigned __int64 ull;
} decomposer;

typedef unsigned int func_t(unsigned __int64 &, unsigned __int64 &);

unsigned int f0001(unsigned __int64 &state, unsigned __int64 &state2);
unsigned int f0002(unsigned __int64 &state, unsigned __int64 &state2);
unsigned int f0003(unsigned __int64 &state, unsigned __int64 &state2);

func_t *g_fptr_array[40] = 
{     0, f0001, f0002, f0003,     0,     0,     0,     0,     0,     0,
      0,     0,     0,     0,     0,     0,     0,     0,     0,     0,
      0,     0,     0,     0,     0,     0,     0,     0,     0,     0,
      0,     0,     0,     0,     0,     0,     0,     0,     0,     0
};

int main(int argc, char **argv)
{
	unsigned int index = 1;
	unsigned __int64 state = 0;
	unsigned __int64 state2 = 0;
	func_t *cfp = NULL;

	for(;;)
	{
		cfp = g_fptr_array[index];
		if(cfp == NULL)
		{
			break;
		}

		index = (*cfp) (state, state2);
	}

	cout << "Press any key to continue.\n";
	_getch();

	return 0;
}

unsigned int f0001(unsigned __int64 &state, unsigned __int64 &state2)
{
	static unsigned int sm1, sm2;
	decomposer dc, dc2;
	dc.ull = state;
	dc2.ull = state2;

	if(dc2.ul.msb == 0)
	{
		cout << "Please enter the first number to be multiplied: ";
		cin >> sm1;
		cout << "Please enter the second number to be multiplied: ";
		cin >> sm2;
	}
	else if(dc2.ul.msb == 1)
	{
		dc.ul.lsb = sm1;
		dc2.ul.msb = 1;
	}
	else if(dc2.ul.msb == 2)
	{
		dc.ul.lsb = sm2;
		dc2.ul.msb = 2;
	}
	else if(dc2.ul.msb == 3)
	{
		sm1 = 0;
		sm2 = 0;
	}

	state = dc.ull;
	state2 = dc2.ull;

	return 2;
}

unsigned int f0002(unsigned __int64 &state, unsigned __int64 &state2)
{
	static bool b1 = false, b2 = false;
	static unsigned int sm1, sm2;
	decomposer dc, dc2;
	dc.ull = state;
	dc2.ull = state2;

	if(dc2.ul.msb == 0)
	{
		if(b1 == false)
		{
			dc2.ul.msb = 1;
		}
		else if(b2 == false)
		{
			dc2.ul.msb = 2;
		}
		else
		{
			dc2.ul.msb = 3;
		}
	}
	else if(dc2.ul.msb == 1)
	{
		sm1 = dc.ul.lsb;
		dc2.ul.msb = 0;
		b1 = true;
	}
	else if(dc2.ul.msb == 2)
	{
		sm2 = dc.ul.lsb;
		dc2.ul.msb = 0;
		b2 = true;
	}
	else if(dc2.ul.msb == 3)
	{
		dc2.ul.lsb = sm1 * sm2;
	}

	state = dc.ull;
	state2 = dc2.ull;
	
	if(dc2.ul.msb == 0)
	{
		return 2;
	}
	else if(dc2.ul.msb < 3)
	{
		return 1;
	}
	else
	{
		return 3;
	}
}

unsigned int f0003(unsigned __int64 &state, unsigned __int64 &state2)
{
	static bool b1 = false;
	static unsigned int sm1;
	decomposer dc, dc2;
	dc.ull = state;
	dc2.ull = state2;

	if(dc2.ul.msb == 3)
	{
		if(b1 == false)
		{
			dc2.ul.msb = 3;
			b1 = true;
		}
		else
		{
			sm1 = dc2.ul.lsb;
			dc2.ul.msb = 1;
		}
	}
	else if(dc2.ul.msb == 1)
	{
		cout << "The two numbers multiplied equal: " << sm1 << endl;
		dc2.ul.msb = 0;
	}

	state = dc.ull;
	state2 = dc2.ull;

	if(dc2.ul.msb == 1)
		return 3;
	else if(dc2.ul.msb == 3)
		return 2;
	else
		return 0;
}