-- File: demo1.ada
-- Demonstrate :
--	Arrays
--	Loops
--	Subprograms: Procedures & Functions
--	Tick Marks
--	Ranges
--	IN membership
--	Boolean Operator

WITH Text_IO;
USE Text_IO;

PROCEDURE demo1 IS

 package Number is new Integer_IO (Integer);  -- pkg for reading int
 use Number;

 type IntList is array (1..10) of Integer;

 List			: IntList; 
 Index, Value		: Integer;

 FUNCTION GetElt(aList: in IntList; index :in Integer) return Integer is
 BEGIN
 	return(aList(index));
 END GetElt;

 PROCEDURE SetElt(aList: IN OUT IntList; index , value: IN Integer) is
 BEGIN
	aList(index):=value;
 END SetElt;

 PROCEDURE PrintList(aList: IN IntList) is
 BEGIN
 	Text_IO.Put(Item=>"Items in the array");
 	Text_IO.New_Line;

 	-- Example of tick mark for low & high
 	for i in List'First .. List'Last Loop
		Put(List(i),0); -- min field width
		Text_IO.Put(" ");
 	END Loop;
 	Text_IO.New_Line;
 END PrintList;

BEGIN -- code of main procedure
 -- Example of tick mark for entire range
 for i in List'Range Loop
	List(i):=i;
 END Loop;
 
 PrintList(List);

 -- Example of do loop; wait! No do loop...must use while
 --	for this example, must be sentinel terminated
 Text_IO.Put("You may change values...");
 Text_IO.Put("Enter the Index to Alter (0 Quits) >");
 Get(Index);
 -- Loop while not sentinel and Index in legal range
 while Index /= 0 AND Index IN List'Range loop
	Text_IO.Put("Present Value: ");
	Put(GetElt(List,Index));
	Text_IO.New_Line;
 	Text_IO.Put("Enter the Value >");
	Get(Value);
	SetElt(List,Index,Value);
	PrintList(List);
 	Text_IO.Put("Enter the Index to Alter (0 Quits) >");
 	Get(Index);
 END Loop;
 Text_IO.New_Line;

END demo1;