#!/usr/bin/perl

use strict;
use warnings;

sub read_file {
    undef $/;
    open my $file, shift;
    my $line=lc<$file>;
    $line=~s/\s//g;
    our @sifrat=split '', $line;
}

sub transpose {
    our @sifrat;
    my @key=split '', shift;
    my $m=@key;
    my $n=(@sifrat)/$m;
    
    for (my $i=0; $i<$n; $i++) {
	foreach (@key) {
	    print $sifrat[($_-1)*$n+$i];
	}
    }
    print "\n";
}

read_file shift @ARGV;
transpose @ARGV;