INPUT FILE: square.in
Given a number of rectangular boxes, draw them all, filled in blue in graphics mode, and draw the outline of the resulting shape in red. The outline should follow the edge between the blue shape and the black background, and be drawn on the blue shape. Use the 640 by 480, 16 colour VGA graphics mode.
INPUT
The input consists of a series lines each containing four integers x1
y1 x2 y2 indicating the coordinates of a box to be drawn.
OUTPUT
Output the blue boxes with the resulting shape(s) outlined in red.
NOTES
To access graphics mode use
var gd, gm: integer;
gd := detect;
InitGraph(gd, gm, 'c:\tp\bgi')
To draw a box filled in blue use
SetFillStyle(SolidFill, Blue);
...
Bar(x1, y1, x2, y2);
To put/get a pixel from the screen use
PutPixel(x, y);
GetPixel(x, y, colour);
Sample Input File
100 100 200 200 200 100 400 400
Output for Sample Input
Shown on the left is the inital shape, and shown on the right is the outlined shape (what your program should show. Note that all corners are outlined! Also note the blue area gets smaller after outlining.