Thread: Draw a grid using the following characters?

You should consider using a multidimensional array (have a read).

Why are you starting the variables at -1 in your loops?

Um, hello! is random_grid_char a function? Sorry, not really good with C yet.

Originally Posted by programmingnewb

Um, hello! is random_grid_char a function? Sorry, not really good with C yet.

Nope. You need to write it yourself.

I meant, I'd need to write it as a function?

Originally Posted by programmingnewb

I meant, I'd need to write it as a function?

If you like. It would be a one line function so you could just as easily do it without.

Oh, okay, thank you sir!

Originally Posted by Matticus

You should consider using a multidimensional array (have a read).

Why are you starting the variables at -1 in your loops?

^^^^ Good advice there.

This is not code for a program. This is code to nudge you in the right direction, only. Fresh off the cuff, and won't compile as is, but it should get you started OK.

Code:

#include <time.h>


#define ROWS 8
#define COLS 8


srand(time());

char grid[ROWS][COLs], temp;
int r, c, r1,c1,i;

//initialize the board grid
for(r=0;r<ROWS;r++) {
   for(c=0;c<COLS;c++) {
      if(r<2 )
          grid[r][c]='@';
      else if(r<4)
          grid[r][c]='#';
      else if(r<6)
          grid[r][c]='*';
      else
          grid[r][c]='!';
   }
}

//now randomize the grid by making a lot of random swaps
for(i=0;i<100;i++) {
    r=rand() % ROWS;
    c=rand() % COLS;
    r1=rand() % ROWS;
    c1=rand() % COLS;
    temp = grid[r][c];
    grid[r][c]= grid[r1][c1];
    grid[r1][c1]=temp;
}

Hi sir/maam! What are the r < 2, r < 4, for?

Originally Posted by Adak

^^^^ Good advice there.

This is not code for a program. This is code to nudge you in the right direction, only. Fresh off the cuff, and won't compile as is, but it should get you started OK.

Code:

#include <time.h>


#define ROWS 8
#define COLS 8


srand(time());

char grid[ROWS][COLs], temp;
int r, c, r1,c1,i;

//initialize the board grid
for(r=0;r<ROWS;r++) {
   for(c=0;c<COLS;c++) {
      if(r<2 )
          grid[r][c]='@';
      else if(r<4)
          grid[r][c]='#';
      else if(r<6)
          grid[r][c]='*';
      else
          grid[r][c]='!';
   }
}

//now randomize the grid by making a lot of random swaps
for(i=0;i<100;i++) {
    r=rand() % ROWS;
    c=rand() % COLS;
    r1=rand() % ROWS;
    c1=rand() % COLS;
    temp = grid[r][c];
    grid[r][c]= grid[r1][c1];
    grid[r1][c1]=temp;
}

I guess you could do it that way. It's a complicated way, though.

Do you have any idea what the r < 2, r < 4 are supposed to be?

Originally Posted by programmingnewb

Do you have any idea what the r < 2, r < 4 are supposed to be?

Not really, sorry :-(

I sent Adak a PM showing him how I'd do it, but I don't want to be seen as giving the answer to you :-(

It really is a simple as using a 1-dimensional array and "addressing" it yourself using either row-major or column-major arithmetic (it doesn't matter which). Personally I wouldn't use a 2-dimensional array for this, but *shrug*.

Oh,it's okay! But everyone I've asked (programmers from League of Legends I befriended) said I should use a 2D array I'll just try to figure it out XD

I did write an example. It can be done better, but it'll work.

Code:

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

#define LENGTH 8
#define WIDTH  8

static const char grid_chars[] = {'!', '@', '#', '$', '&'};
static const int num_grid_chars = sizeof grid_chars / sizeof grid_chars[0];

char random_grid_char(void)
{
    return grid_chars[rand() % num_grid_chars];
}

void makegrid(char *grid)
{
    int j;
    int k;

    for (j = 0; j < LENGTH; j++)
    {
        for (k = 0; k < WIDTH; k++)
        {            
            grid[j * LENGTH + k] = random_grid_char();
        }
    }
}

void printgrid(char *grid)
{
    int j;
    int k;

    for (j = 0; j < LENGTH; j++)
    {
        for (k = 0; k < WIDTH; k++)
        {
            printf("%c", grid[j * LENGTH + k]);
        }
        printf("\n");
    }
}

int main(void)
{
    char grid[WIDTH * LENGTH];
    makegrid(grid);
    printgrid(grid);
    return 0;
}