Program to read ages into array using procedure
Write out data using another procedure 

	program procio;
	type
	    ara500 = array[1..500] of real;
	var
	    ages: ara500;
	    n: integer;
	
	procedure indata(var info: ara500; var count: integer);
	    var
		k: integer;
		years: real;
	    begin
	    k := 0;
	    writeln('Age?');
	    readln (years);
	    while years > 0.0 do
		begin
		k := k + 1;
		info[k] := years;
	        writeln('Age?');
	    	readln (years);
		end;
	    count := k;
	    end; {indata};
		
	procedure outdata(var info: ara500; var count: integer);
	    var
		k: integer;
		years: real;
	    begin
	    k := 0;
	    while k < count do
		begin
		k := k + 1;
	        writeln(info[k]:5:1);
		end;
	    end; {outdata};
		
	begin
	indata(ages, n);
	outdata(ages, n);
	writeln('***':5);
	outdata(ages, n);
	readln;
	end.

Sample output:

>Age?
<22.0
>Age?
<18.5
>Age?
<21.5
>Age?
<0.0
> 22.0
> 18.5
> 21.5
>  ***
> 22.0
> 18.5
> 21.5