Program to read ages into array as long as values are greater
than sentinal value.  (note that in contrast to class, reals
rather than integers are used for the data.  Also the array can
hold up to 500 values, not just 20.  This program is probably
slightly more elegant than the one written on the fly in class,
but that's a matter of taste.


	program inout;
	type
		ara500 = array[1..500] of real;
	var
		ages: ara500;
		sentinel, age: real;
		i, n: integer;
	begin
	sentinel := 0.0;
	n := 0;
	writeln('Enter age or 0.0 to quit.');
	readln(age);
	while  age > sentinel do
		begin
		n := n + 1;
		ages[n] := age;
		writeln('Enter age or 0.0 to quit.');
		readln(age);
		end;
	writeln(n, ' ages entered.');
	i := 0;
	while i > n do
		begin					{alternate code}
		i := i + 1;
		age := ages[i];				{ <- omit }
		writeln(age:5:1);			writeln(ages[i]:5:1);
		end;
	readln;
	end.

Sample output:

>Enter age or 0.0 to quit.
<2.0
>Enter age or 0.0 to quit.
<28.0
>Enter age or 0.0 to quit.
<11.5
>Enter age or 0.0 to quit.
<17.0
>Enter age or 0.0 to quit.
<0.0
>4 ages entered.
>  2.0
> 28.0
> 11.5
> 17.0



Previous program with the following additions:
1. Find the maximum and minimum age.
2. Count the number of people older than 65.
3. Adds together the total years in excess of 65.
It also goes through the array in reverse order (larger subscript
to smaller) and thus lists the ages in revers order

	program inout;
	type
		ara500 = array[1..500] of real;
	var
		ages: ara500;
		sentinel, age, max, min, excess: real;
		i, n, older: integer;
	begin
	sentinel := 0.0;
	n := 0;
	writeln('Enter age or 0.0 to quit.');
	readln(age);
	while  age > sentinel do
		begin
		n := n + 1;
		ages[n] := age;
		writeln('Enter age or 0.0 to quit.');
		readln(age);
		end;
	writeln(n, ' ages entered.');
	i := n;
	max := ages[1];
	min := ages[1];
	older := 0;
	excess := 0.0;
	while i > 0 do				{Alternate code}
		begin
		age := ages[i];			{ <- omit}
		writeln(age:5:1);		writeln(ages[i]:5:1);
		if age > max then		if ages[i] > max then
			begin
			max := age;			max := ages[i];
			end;
		if age < min then		if ages[i] < min then
			begin
			min := age;			min := ages[i];
			end;
		if age > 65.0 then		if ages[i] > 65.0 then
			begin
			older := older + 1;	
			excess := excess + age - 65.0;
						excess := excess+ages[i]-65.0;
			end;
		i := i - 1;
		end;
	writeln('Max =', max:5:1, ' Min =', min:5:1);
	writeln('Number older than 65 =', older:5);
	writeln('Total years in excess of 65 =', excess:5:1);
	readln;
	end.

Sample output:

>Enter age or 0.0 to quit.
<77.5
>Enter age or 0.0 to quit.
<88.0
>Enter age or 0.0 to quit.
<61.5
>Enter age or 0.0 to quit.
<28.0
>Enter age or 0.0 to quit.
<67.0
>Enter age or 0.0 to quit.
<0.0
>5 ages entered.
> 67.0
> 28.0
> 61.5					<- note reversed ordeer
> 88.0
> 77.5
>Max = 88.0 Min = 28.0
>Number older than 65 =    3
>Total years in excess of 65 = 37.5



Previous program with the following additions:
1. Find the maximum and minimum age.
2. Count the number of people older than 65.
3. Adds together the total years in excess of 65.
It also goes through the array in reverse order (larger subscript