Question

Write a prograrm that generates a "random walk" across a 10 × 10 array. The array will con- tain characters (all ' . ' initially). The program must randomly "walk" from element to ele- ment, always going up, down, left, or right by one element. The elements visited by the program will be labeled with the letters A through Z, in the order visited. Here's an example of the desired output: 9. BCD.. F E. H G KR S T U V Y N O Hint: Use the srand and rand functions (see deal.c) to generate random n After generating a number, look at its remainder when divided by 4. There are four possible values for the remainder-0, 1, 2, and 3-indicating the direction of the next move. Before performing a move, check that (a) it won't go outside the array, and (b) it doesn't take us to
C Programming.

Answer 1

Explanation:

This program will give us the random genarated values in the out put. Please find the attached out put screen shot for one of the random generated out put pattern.

Program:

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

#define ROWSOBJ 10
#define COLSOBJ 10
int main (void) {

int iObj, jObj, kObj, directionObj;
char boardObj[ROWSOBJ][COLSOBJ];
const char lettersObj[] = {'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 (iObj = 0; iObj < ROWSOBJ; iObj++)
for (jObj = 0; jObj < COLSOBJ; jObj++)
boardObj[iObj][jObj] = '.';

iObj = 0;
jObj = 0;
kObj = 1;
boardObj[iObj][jObj] = lettersObj[0];
while (kObj < 26) {
directionObj = rand() % 4;
switch (directionObj) {
case 0: if (boardObj[iObj][jObj + 1] == '.' && jObj != ROWSOBJ - 1){
boardObj[iObj][jObj +1] = lettersObj[kObj];
kObj++; jObj++;}
if (boardObj[iObj][jObj + 1] != '.' && boardObj[iObj + 1][jObj] != '.' && boardObj[iObj - 1][jObj] != '.' && boardObj[iObj][jObj - 1] != '.')
kObj = 27;
break;   
case 1: if (boardObj[iObj + 1][jObj] == '.' && iObj != COLSOBJ -1) {
boardObj[iObj + 1][jObj] = lettersObj[kObj];
kObj++; iObj++; }
if (boardObj[iObj][jObj + 1] != '.' && boardObj[iObj + 1][jObj] != '.' && boardObj[iObj - 1][jObj] != '.' && boardObj[iObj][jObj - 1] != '.')
kObj = 27;
break;
case 2: if (boardObj[iObj - 1][jObj] == '.' && iObj != 0){
boardObj[iObj - 1][jObj] = lettersObj[kObj];
kObj++; iObj--; }
if (boardObj[iObj][jObj + 1] != '.' && boardObj[iObj + 1][jObj] != '.' && boardObj[iObj - 1][jObj] != '.' && boardObj[iObj][jObj - 1] != '.')
kObj = 27;
break;
case 3: if (boardObj[iObj][jObj - 1] == '.' && jObj != 0) {
boardObj[iObj][jObj - 1] = lettersObj[kObj];
kObj++; jObj--;}
if (boardObj[iObj][jObj + 1] != '.' && boardObj[iObj + 1][jObj] != '.' && boardObj[iObj - 1][jObj] != '.' && boardObj[iObj][jObj - 1] != '.')
kObj = 27;
break;
}
}
for (iObj = 0; iObj < ROWSOBJ; iObj++) {
for (jObj = 0; jObj < COLSOBJ; jObj++)
printf ("%4c", boardObj[iObj][jObj]);
printf ("\n");
}

return 0;

}

Output screenshot: