#!/usr/bin/perl
sub E{print "Chyba: file descriptor $_[1] neni pripraven pro ".($_[0]?"zapis":"cteni")."!\n";exit 1;}
print STDERR "Heslo je: \n" or E(1,2);open(B, ">&=5") or E(1,5);select((select(B), $|=1)[0]);open(A, "<&=6") or E(0,6);print B "ymozaujkdlrrsltpwfgnhj\n";
while (<A>){print STDERR and exit 0 or E(1,2)if (y/a-z// <= 7);eval "y(.".("."x(y{aeiouy}()))."a-z).".("a-z"x 5).".";$x="."x($.%3);s/^$x//;print B;}