Thread: Program that generates a "random walk" across 10*10 array

ThebigH - I don't wanna do a bigger array cause the question asks for a 10*10

iMalc - i reversed as per your advise and works well....gonna go read about "short circuit evauation" now

ok. i get it......I didn't think that through....thought because it's OR then the order won't matter, but you're right.

OK. I think I'm done now thks.

Originally Posted by quzah

posts #3, 11, 27. I only told you three times!


Quzah.

tks quzah

Originally Posted by danieldcc

oh man, Tater, I think you're too advance for me.

iMalc - i think i want to do it this way
1. You could 'or' a bounds test in with each 'anded' test for a dot in that spot.

can you give me a little more clue on that

Ok, you're 33 messages into this thing and no closer to a solution... Will you at least try my suggestion from post #23...

No closer to a solution? I got my solution already I believe.

Code:

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

#define ROWS 10
#define COLS 10
int main (void) {

int i, j, k, direction;
char board[ROWS][COLS];
const char letters[] = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'};

srand ((unsigned) time(NULL));

for (i = 0; i < ROWS; i++)
  for (j = 0; j < COLS; j++)
    board[i][j] = '.';

i = 0;
j = 0;    
k = 1;
board[i][j] = letters[0];  //set array[0][0] to first element 
while (k < 26) {
  direction = rand() % 4;
  
if (board[i][j] == '.')
board[i][j] = letters[k++];  
if ((j == ROWS - 1 || board[i][j + 1] != '.') && (i == COLS -1 || board[i + 1][j] != '.') && (i == 0 || board[i - 1][j] != '.') 
    && (j == 0 ||board[i][j - 1] != '.' ))
break;
    switch (direction) {
      case 0: if (j < ROWS - 1 && board[i][j + 1] == '.'){  //move right
              j++;
              break;     }
      case 1: if (i < COLS -1 && board[i + 1][j] == '.') {  //move down
              i++;
              break; }
      case 2: if (i > 0 && board[i - 1][j] == '.'){  //move up
              i--;
              break;  }    
      case 3: if (j > 0 && board[i][j - 1] == '.') { //move left
              j--;
              break; }
}
}
for (i = 0; i < ROWS; i++) {
  for (j = 0; j < COLS; j++)
    printf ("%4c", board[i][j]);
  printf ("\n");
}

return 0;

}

Originally Posted by danieldcc

oh man, Tater, I think you're too advance for me.

Modulus is actually a very simple operation. a % b == the remainder of a / b. So the subscript is never greater than b. When b is an array size, that's a good thing.