General C questions

vargadanis · 09-19-2006, 03:21 PM

Hi all...

I am new to programming in C. I have just now bought a book. ^_^
So I have a 3D array with numbers in it from 0 to 9. The sequence of numbers are random. The main point of the "game" is to organize these into the right sequence: 0,1,2,3,4,5,6,7,8.
You can do this by pressing A,S,D or W keys. The 0 is not displayed. Instead there is space. So my problem is that I do not really know how to check the keyboard for the input. I tryed ti use scanf and do{}while but it does not really work good because I have to press RETURN every time I enter a letter.
So how can I avoid pressing RETURN each time? I tryed to use getchar but no success.
Here is the code. Might be messy. Embarrassed
Code:

Code:

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

int a[3][3] = {{0,3,6},{1,4,7},{2,5,8}};    
int i,j,tmp,x,y;
char c, chr;

void anything()
{
     for (i=0; i<3; i++){
      for (j=0; j<3; j++){
          if (a[i][j]==0){
             printf ("  ");
             x = i;
             y = j;
          }else{
             printf("%d ", a[i][j]);
          }
          
      }
      printf ("\n");
  }
  
  return;
}
void moveA(){
    if(y>0){
        tmp=a[x][y];
        a[x][y]=a[x][y-1];
        a[x][y-1]=tmp;                 
        printf("\n");         
        anything();                             
    }else{
        printf("\nThis is an invalid movement. \n");
        anything();
    }
}
void moveD(){
    if(y<2){
        tmp=a[x][y];
        a[x][y]=a[x][y+1];
        a[x][y+1]=tmp;                 
        printf("\n");         
        anything();                             
    }else{
        printf("\nThis is an invalid movement. \n");
        anything();
    }
}
void moveS(){
    if(x<2){
        tmp=a[x][y];
        a[x][y]=a[x+1][y];
        a[x+1][y]=tmp;
        anything();
    }else{
        printf("\nThat is an invalid movement. \n");
        anything();
    }
}
void moveW(){
    if(x>0){
        tmp=a[x][y];
        a[x][y]=a[x-1][y];
        a[x-1][y]=tmp;
        anything();
    }else{
        printf("\nThis is an invalid movemenet.\n");
        anything();
    }
}
void test(){    
    if(a[0][0]==0 && a[0][1]==1 && a[0][2]==2 && a[1][0]==3 && a[1][1]==4 && a[1][2]==5 && a[2][0]==6 && a[2][1]==7 && a[2][2]==8){        
        printf("\n\n CONGRATULATIONS\n");
    }else{
        printf("\nNot now...\n");
    }
    return;
}
int main()
{

  printf("COOL \t GAME. \t ^_^\n");
  printf("Press A to move the space to left, D to right, W to up and S to down. q to exit..\n");
  printf("If you think you have finished press T (test)\n");
  printf("____________________________________________\n\n");
  anything();
  do{
      scanf("%c", &c);
      switch(c){
          case 97:    moveA(); break;
          case 100: moveD(); break;
          case 115:    moveS(); break;
          case 119:    moveW(); break;
          case 116: test();  break;
      }
  }while(c!=113);
  system("PAUSE");    
  return 0;
}

I wrote it under windows but I used MinGW compiler (gcc) to be sure that it can be run on linux after compiling too.

Dani

pda_h4x0r · 09-19-2006, 04:28 PM

Use SDL to read the keyboard.

Here's a sample:

Code:

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

int main(int argc, char** argv) {

if(SDL_Init() < 0) return 0;  //error

unsigned char* keyboard;

do {

keyboard = SDL_GetKeyState(NULL);

//index keyboard by SDLK_<keyname>
if(keyboard[SDLK_RETURN]) printf("You hit enter!\n");
if(keyboard[SDLK_SPACE]) printf("You hit space!\n");
if(keyboard[SDLK_a]) printf("You hit A!\n");
if(keyboard[SDLK_w]) printf("You hit W!\n");
if(keyboard[SDLK_s]) printf("You hit S!\n");
if(keyboard[SDLK_d]) printf("You hit D!\n");
if(keyboard[SDLK_q]) printf("You hit Q!\n");

} while (!keyboard[SDLK_q]);

SDL_Quit();

return 0;

}

You will need to include the paths to the SDL include files and libs--use the sdl-config command to get these (assuming you have actually installed SDL in the first place).

tuxdev · 09-19-2006, 04:57 PM

If ye wishes not ta use SDL, ye can use this code ta start taking input unbuffered

Code:

   /* set terminal in raw mode */
   struct termios cur,raw;
   tcgetattr(STDIN_FILENO,&cur);
   raw=cur;
   raw.c_lflag&=~(ICANON|ECHO|ISIG);
   raw.c_cc[VMIN]=1;
   raw.c_cc[VTIME]=0;
   tcsetattr(STDIN_FILENO,TCSAFLUSH,&raw);

th'n ask fer input using getchar(), then finish with

Code:

   /* restore and terminate */
   tcsetattr(STDIN_FILENO,TCSAFLUSH,&cur);

And if ye be asking, today be Talk Like a Pirate day.

pankaj99 · 09-19-2006, 05:20 PM

this guy is new to C programing and you guys are suggesting him to use SDL etc?

vargadanis,
Standard C does not provide any mechanism to do what you
want.
Your array is 2D not 3D.

vargadanis · 09-19-2006, 06:02 PM

You are rite, pankaj99. ^_^
I solved it with _getch() function from conio.h. I do not not what is that SDL thing so I was thinking on the alternatives of conio.h under linux. Any ideas?

tuxdev · 09-19-2006, 06:08 PM

ye ignored me post. Me code puts th' console into "cooked" mode, where th' characters typed are not echoed and immediately available ta getchar(). _getch() be a reserved name, don't use it.

vargadanis · 09-19-2006, 06:15 PM

I have just now found the perfect sollution.
include <ncuses.h>

than use getch() function. Works perfectly. ^_^

tuxdev · 09-19-2006, 06:20 PM

Ye needs ncurses for that, and ncurses is overkill in this case. Ye can print '\r' ta go back ta th' begining of th' line ye are printing, and print over what ye needs ta, and place th' cursor on th' line. Ye should also use 'w', 'a', 's', and 'd' instead of numerical constants because th' numbers may mean diffrent things based on th' text encoding, e.g. EBCDIC.

vargadanis · 09-19-2006, 08:04 PM

you are rite... I tried to use "" marks instead of ''. It did not work but with '' worked prperly. That is ok...
I said it works perfectly... It should work perfectly but it doesn't. I installed libncurses5.deb from the packages.ubuntu.com site and tried to include ncurses.h without any success. Why isn't it working? What else shall I install?

pankaj99 · 09-20-2006, 01:13 AM

what you are trying to do is not in the standard C language.
The header file <ncurses.h> is not defined by the std C.
http://en.wikipedia.org/wiki/C_standard_library.

To compile using ncurses ,you have to link against the ncurses library
in the command line.

vargadanis · 09-20-2006, 10:32 AM

Cool.... And how?

dive · 09-20-2006, 11:28 AM

Quote:

Originally Posted by vargadanis

Cool.... And how?

-lncurses in the compile command line

ntubski · 09-20-2006, 11:43 AM

Also make sure you installed the libncurses-dev package