MODULE selectchar0;
(*---------------------------------------------------------
File name: selectchar0.pm
Author: AG
Date: 10/06/05 

Problem: Selects characters from a chain of CHAR, then copies
the selected  characters into another chain.

Example of Execution: 
Before:
L2ch	:  aaaaaaaaaaaaaaa
L3ch	:  bbbbbbbbbbbbbbb

After:
L2ch  :  aaaaaaaaaaaaaaa
L1bool:   0  1  0  0  1  0  0  1  0  0  1  0  0  1  0
L3ch  :  babbabbabbabbab


Cycles:
1 selection + 1 assignment

*)
(*----------------------------------------------------------					
		CONFIGURATION
----------------------------------------------------------*)
CONST  MAXCELLS=1024; (* MAXCELLS cells in one line *)

CONFIGURATION chain[0..(MAXCELLS - 1)];
CONNECTION
		left: chain [i] -> chain[(i-1) MOD MAXCELLS];
		right: chain[i] -> chain[(i+1) MOD MAXCELLS];
(*----------------------------------------------------------
		VARIABLES
-----------------------------------------------------------*)
VAR 
		L1bool: chain OF INTEGER;
		L2ch, L3ch:	chain OF CHAR;
		N, RightLimit: INTEGER;
		
(*--------------------------------------------------------
		MAIN
-----------------------------------------------------------*)
BEGIN
	(* initializing data *)
	L2ch := 'a';
	L3ch:= 'b';
	N:= 3;
	RightLimit:= 16;
	
	IF ID(chain) MOD N = 2 THEN
		L1bool := 1;
	END; (* IF *)
	
	IF ID(chain) < RightLimit THEN
		IF L1bool = 1 THEN
			L3ch := L2ch;
		END; (* IF  *)
		
		(* printing *)
		WriteString( " L2ch  :  ");Write( L2ch); WriteLn;
		WriteString( " L3ch  :  ");Write( L3ch); WriteLn;
		WriteString( " L1bool:  ");WriteInt( L1bool ,  2); WriteLn;
	END; (* IF *)
END selectchar0.