randomwalk.c

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

int main (void) {
// Initialize 10x10 matrix
char Area[10][10];
for (int i = 0; i < 10; i++) {
	for (int j = 0; j < 10; j++) {
		Area[i][j] = '.';
		}
	}
// up = 0 = row-1 | down = 1 = row+1 | right = 2 = col+1 | left = 3 = col-1
// Begin movement at [0][0]

srand(time(NULL));
int col = 0;
int row = 0;
int movement;
int legal;
int legalmoves[4] = {1,1,1,1}; // 1 = legal move, 0 = illegal move, up,down,right,left respectively
int Space[10][10] = {0}; // 0 = empty space, 1 = space occupied by letter
Area[row][col] = 'A'; //put A at [0][0]
Space [0][0] = 1;

for (int k = 'B'; k <= 'Z' ; k++) {
// Find illegal moves
if (row - 1 < 0 || Space[row-1][col] == 1) {
legalmoves[0] = 0; //cant go up
	}
if (row + 1 >= 10 || Space[row+1][col] == 1) {
legalmoves[1] = 0; //cant go down
	}
if (col + 1 >= 10 || Space[row][col+1] == 1) {
legalmoves[2] = 0; // cant go right
	}
if (col - 1 < 0 || Space[row][col-1] == 1) {
legalmoves[3] = 0; //cant go left
	}

if (legalmoves[0] == 0 && legalmoves[1] == 0 && legalmoves[2] == 0 && legalmoves[3] == 0)
	break; //stop program if no legal moves found

// Check if the random movement is legal, if not try again.
legal = 0;
while (legal == 0) {
movement = rand()%4;
switch (movement)
{
case 0: //up
	if (legalmoves[0] == 0)
		continue;
		else
		legal = 1;
		break;
case 1: //down
	if (legalmoves[1] == 0)
		continue;
		else
		legal = 1;
		break;
case 2: //right
	if (legalmoves[2] == 0)
		continue;
		else
		legal = 1;
		break;
case 3: //left
	if (legalmoves[3] == 0)
		continue;
		else
		legal = 1;
		break;
	}
}

// Begin movement
switch (movement)
{
case 0:
	row = row-1;
	break;
case 1:
	row = row+1;
	break;
case 2:
	col = col+1;
	break;
case 3:
	col = col-1;
	break;
}
Area[row][col] = k;
Space[row][col] = 1;
// re-initialize legalmoves array back to 1's
for (int initialize = 0; initialize < 4; initialize++) {
legalmoves[initialize] = 1;
	}

	}
// Print the area and path
for (int l = 0; l < 10; l++) {
	for (int m = 0; m < 10; m++) {
		printf("%c	",Area[l][m]);
		}
	printf("\n\n");

}
return 0;
	}