#include <stdio.h>
//#include <conio.h>
#include <time.h>
//#include <disp.h>
//
#define MAX_ROW 8
#define MAX_COL 8
#define MAX_HORSE_STEPS 8
#define HORSE_ROW 2
#define HORSE_COL 1
//
int Board[MAX_ROW][MAX_COL] = {0};
int maxPos = (MAX_ROW * MAX_COL);
int AvalSteps[8][2];
int currentPos = 0;
long currentTry = 1;
//
void fn_show_current_board(void);
void fn_next_step(int, int);
int fn_check_closest_cells(void);
int fn_next_cell(int *, int *);
//
/*--------------------------------------------------
*/
int main()
{
	time_t start_time;
	time_t end_time;
	int ir, firt_r = 0;
	int ic, firt_c = 0;
	char pkey;
	//
	// Возможные шаги коня
	AvalSteps[0][0] = -HORSE_ROW;
	AvalSteps[0][1] = +HORSE_COL;
	AvalSteps[1][0] = -HORSE_COL;
	AvalSteps[1][1] = +HORSE_ROW;
	AvalSteps[2][0] = +HORSE_COL;
	AvalSteps[2][1] = +HORSE_ROW;
	AvalSteps[3][0] = +HORSE_ROW;
	AvalSteps[3][1] = +HORSE_COL;
	AvalSteps[4][0] = +HORSE_ROW;
	AvalSteps[4][1] = -HORSE_COL;
	AvalSteps[5][0] = +HORSE_COL;
	AvalSteps[5][1] = -HORSE_ROW;
	AvalSteps[6][0] = -HORSE_COL;
	AvalSteps[6][1] = -HORSE_ROW;
	AvalSteps[7][0] = -HORSE_ROW;
	AvalSteps[7][1] = -HORSE_COL;
	//
repeat_more:
	//disp_setmode(3);
	//disp_open();
	//disp_setattr(0x02);
	//
	time(&start_time);
	while (currentPos < maxPos)
	{
		fn_next_step(firt_r, firt_c);
		if (currentPos < maxPos)
		{
			if (!fn_next_cell(&firt_r, &firt_c))
				break;
		}
	}
	time(&end_time);
	//
	//disp_close();
	//
	printf("Ok!\n");
	printf("Start time: %d : %s", (long)start_time, ctime(&start_time));
	printf("End time: %d  : %s", (long)end_time, ctime(&end_time));
	printf("Total seconds: %d\n", (long)(end_time - start_time));
	printf("Do it in next cell? (Y/N)");
	pkey = getchar();
	if (pkey == 'Y' || pkey == 'y')
	{
		for (ir = 0; ir < MAX_ROW; ir++)
		{
			for (ic = 0; ic < MAX_COL; ic++)
			{
				Board[ir][ic] = 0;
			}
		}
		currentPos = 0;
		currentTry = 1;
		if (fn_next_cell(&firt_r, &firt_c))
		{
			goto repeat_more;
		}
		else
		{
			printf("This is the end cell\n");
			getchar();
		}
	}
	return 0;
}
/*--------------------------------------------------
*/
void fn_next_step(int init_r, int init_c)
{
	int step;
	//
	currentTry++;
	// проверка выхода за края доски
	if ((init_r >= 0) && (init_c >= 0) && (init_r < MAX_ROW) && (init_c < MAX_COL))
	{
		// проверка свободного, еще не посещенного поля
		if (Board[init_r][init_c] == 0)
		{
			// проверка отсутствия запертых клеток (или предпоследнего шага)
			if (currentPos == (maxPos - 1) || fn_check_closest_cells() == 1)
			{
				// проверка количества пройденных клето
				if (currentPos < maxPos)
				{
					++currentPos;
					Board[init_r][init_c] = currentPos;
					fn_show_current_board();
					for (step = 0; step < MAX_HORSE_STEPS; step++)
					{
						fn_next_step(init_r + AvalSteps[step][0], init_c + AvalSteps[step][1]);
					}
					if (currentPos < maxPos)
					{
						--currentPos;
						Board[init_r][init_c] = 0;
					}
				}
			}
		}
	}
}
/*--------------------------------------------------
*/
void fn_show_current_board(void)
{
	int ir, ic;
	if ((currentTry >= 1000) || (currentPos >= maxPos))
	{
		currentTry = 1;
		//disp_move(0, 0);
		//disp_printf(" > %d\n", currentPos);
		printf(" > %d\n", currentPos);
		for (ir = 0; ir < MAX_ROW; ir++)
		{
			for (ic = 0; ic < MAX_COL; ic++)
			{
				//disp_printf("| %2d ", Board[ir][ic]);
				printf("| %2d ", Board[ir][ic]);
			}
			//disp_printf("|\n");
			printf("|\n");
			for (ic = 0; ic < MAX_COL; ic++)
			{
				//disp_printf("-----");
				printf("-----");
			};
			//disp_printf("-\n");
			printf("-\n");
		}
		/*
		if (kbhit())
		{
			if (getch() == 'q')
			{
				currentPos = (maxPos + 1);
			}
		}
		*/
	}
}
/*--------------------------------------------------
*/
int fn_check_closest_cells(void)
{
	int ir, ic, step, ch_r, ch_c, ok_flag;
	for (ir = 0; ir < MAX_ROW; ir++)
	{
		for (ic = 0; ic < MAX_COL; ic++)
		{
			if (Board[ir][ic] == 0)
			{
				ok_flag = 0;
				for (step = 0; step < MAX_HORSE_STEPS; step++)
				{
					ch_r = ir + AvalSteps[step][0];
					ch_c = ic + AvalSteps[step][1];
					if ((ch_r >= 0) && (ch_c >= 0) && (ch_r < MAX_ROW) && (ch_c < MAX_COL))
					{
						if (Board[ch_r][ch_c] == 0)
						{
							ok_flag = 1;
							break;
						}
					}
				}
				if (ok_flag == 0)
				{
					return 0;
				}
			}
		}
	}
	return 1;
}
/*--------------------------------------------------
*/
int fn_next_cell(int *r, int *c)
{
	(*r)++;
	if ((*r) > (MAX_ROW - 1))
	{
		(*r) = 0;
		(*c)++;
		if ((*c) > (MAX_COL - 1))
		{
			return 0;
		}
	}
	return 1;
}
/*--------------------------------------------------
*/