Timer in Pascal, cycle, tell me?

Question

Pascal

Let's say I made such a simple program:
var
a: longint;
begin
writeln('Enter an integer (max. 2100000000)');
readln(a);
if a mod 2 = 0 then writeln('This number is even')
else writeln('This number is odd');
end.
When launched in the .exe extension, the program closes immediately after execution. Tell me the source code of the timer and how to set an infinite loop (so that the program is constantly repeated).

Answer 1

Wrap everything in a wile loop, and tell the user to e.g. press 0 to exit if non-zero is entered, the loop continues.