Graphics programs

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

void main (int)
{
int gdriver=DETECT,gmode,errorcode; //Requesting auto-detection.
int midx,midy,x;
//Initializing graphics and local variables.
initgraph(&gdriver,&gmode,"d:\\bc3\\bgi");
//Reading result of initialization.
errorcode=graphresult();
if(errorcode!=grOk)
//An error occurred.
{
printf("Graphics error occurred : %s \n",grapherrormsg(errorcode));
printf("Press any key to stop : ");
getch();
exit(1); //Terminate the program due to error.
}

setfillstyle(EMPTY_FILL,0);
/*The above statement means that the setfillstyle function is used to
set the fill style of the 3-d bar as a blank.*/
bar3d(200,200,300,450,10,1);
getch();
closegraph();
}
http://www.syvum.com/cgi/online/serve.cgi/squizzes/cpp/cpp_p19a.html

This program shows pre-defined values.

#include <iostream.h>
#include <conio.h>

void main()
{
  clrscr();
  int x = 10;
  float y = 10.1;
  char z = 'a';
  cout << "x = " << x << endl;
  cout << "y = " << y << endl;
  cout << "z = " << z << endl;
  getch();
}

output:
x = 10
y = 10.1
z = a