MODULE random;
(*---------------------------------------------------------
File name: random.pm
Author: MM
Date: 5/18/05 

Problem: This program limits the size of the chain so that we 
can work in a section of it. We define 'RightLimit' and work only 
with the cells to the left of that one. It then fills that section 
of the array with random numbers.
RandomInt(configuration) is a standard function.

Example of Execution:
	Line is: 2  0  4  3  3  9  9  0  5  9  7  5  5  5

Cycles:
1 MOD + 1 RandomInt
*)
(*----------------------------------------------------------
		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 
		L: chain OF INTEGER;  	(* Line always "L# *)	
		RightLimit: INTEGER;
		MaxVal: INTEGER;
(*----------------------------------------------------------
		MAIN
----------------------------------------------------------*)
BEGIN
	L := ID( chain );
	RightLimit := 15; 		(*work limited to the first 15 cells*)
	MaxVal := 10;		(* maximum value for random *)
	
	IF L < RightLimit THEN		(* work only in selected first 15 cells *)
		L := RandomInt(chain ) MOD MaxVal;  	(* Put random numbers in L *)
		
		(*printing*)
		WriteString( " Line is:  "); WriteInt( L  ,  2); WriteLn;
	END;  (* IF *)
END random.