procedure main()  # validate against the RFC test strings and more
   testMD5("The quick brown fox jumps over the lazy dog", 16r9e107d9d372bb6826bd81d3542a419d6)
   testMD5("The quick brown fox jumps over the lazy dog.", 16re4d909c290d0fb1ca068ffaddf22cbd0)
   testMD5("", 16rd41d8cd98f00b204e9800998ecf8427e)
end

procedure testMD5(s,rh)  # compute the MD5 hash and compare it to reference value
   write("Message(length=",*s,") = ",image(s))
   write("Digest = ",hexstring(h := MD5(s)),if h = rh then " matches reference hash" else (" does not match reference hash = " || hexstring(rh)),"\n")
end