GUESSNUM.P

[Table of Contents]
Disk Image

Many early text-based computer games (BASIC Computer Games, More BASIC Computer Games, etc.) needed the ability to display information (instructions, prompts, results, etc.) to the user, accept information (commands, guesses, etc.) from the user, and usually some kind of pseudo-random number generation. This program, GUESSNUM.P, is a simple example.

String is not a predefined Pascal data type. You can declare a String Type as an array of characters. If you do so, Kyan Pascal includes some String Type handling routines including Length, Index, Substring, and Concatenate.

This program uses the LENGTH.I include file from the Kyan Pascal 2.04 Disk 2 to find the actual length of string. It is used to eliminate trailing spaces when printing strings to the screen.

This program also uses the RANDOMS.I include file from the Kyan Pascal 2.04 Utilities Disk 1 to generate a pseudo-random number between 1 and 20.

What's on the disk?

The disk image includes the various Atari DOS 2.5 files, Kyan Pascal Include files (two of which are used in this program), Kyan Pascal Run-time library, and ...

LENGTH.I - String length functionality include file
RANDOMS.I - Pseudo-random number functionality include file
GUESSNUM.P - Source code file
P.OUT - Kyan Pascal intermediate file
GUESSNUM - Executable file

Source Code

(* Guessnum.p *)
(* Kyan Pascal 2.x / Atari 8-bit *)

Program Guessnum(Input,Output);

Const
   Maxstring = 20;

Type
   String = Array[1..Maxstring] of Char;

Var
   Complete : Boolean;
   Tries : Integer;
   Guess : Integer;
   Number : Integer;
   Guessed :Boolean;
   Name : String;

#I Randoms.i
#I Length.i

(* Main Procedure *)
Begin

   Write(Chr(125)); (* Clear screen *)

   Tries:=0;
   Number:=Random(1,20);

   Guessed:=False;
   Complete:=False;

   Write('Hello. What is your name? ');
   Readln(Name);
   Writeln;

   Writeln('I''m thinking of a number between');
   Writeln('1 and 20. You have six chances to');
   Writeln('guess the number. Good luck, ', Name:Length(Name),'.');
   Writeln;

   While Complete=False DO
   BEGIN
      Write('What is your guess? ');
      Readln(Guess);

      Tries:=Tries+1;

      If Guess = Number Then
      Begin
         Guessed:=True;
         Complete:=True;
      End;

      If Guess < Number Then
         Writeln('Your guess is too low.');

      If Guess > Number Then
         Writeln('Your guess is too high.');

      If Tries=6 Then
         Complete:=True;

      Writeln;
   End;

   If Guessed=True Then
   Begin
      Writeln('Great job. You guessed the number');
      Writeln('in ',Tries,' tries!');
   End;

   If Guessed=False Then
      Writeln('Sorry, you failed to guess the number ', Number,'.');

   Writeln;

   Write('Press <RETURN> to exit program.');
   Readln;
END. (* Guessnum.p *) 

Sample Run