Example: main ()
begin
  write(‘How many pairs?’);
  readln(noPairs);
for i := 1 to noPairs do
  begin
    write(‘Enter first letter of’,
      ‘choice (Gcd, Lcm, Both) ‘,
      ‘then two numbers: ‘);
    readln(choice, oneA,
oneB);
   doIt(choice, oneA, oneB)
  end
end.