$lines

$constant true = FFFFH
$constant false = 0

var n, sq, r = real.double
var done = integer

print "Finding smallest number whose square ends in 269696"

n = 520    rem - no smaller number has a square that large
done = false

rem - no need to search beyond the number Babbage already knew
while not done and n <= 99736.0 do
  begin
    sq = n * n
    rem - compute sq mod 1000000 by repeated subtraction
    r = sq
    while r >= 1000000.0 do
      r = r - 1000000.0
    if r = 269696.0 then
      begin
        print using "The smallest number is ######"; n
        print using "and its square is ##,###,###,###"; sq
        done = true
      end
    rem - only even numbers can have a square ending in 6
    n = n + 2
  end

end