#!/usr/bin/perl

use strict;

my @fibo = (0, 1);

my @text;
push @text, split /\s+/, $_ while <STDIN>;

sub modword {
  my $word = pop;

  return (( ($fibo[-1]-1) % length($word) )+1)
}


foreach my $word (@text) {
  my $space = ' ' if $word =~ /[.!?]/;
  $word =~ s/\W+//g;
  print "\n" and next unless $word;

  print substr($word, modword($word) - 1, 1), $space;
  @fibo = (modword($word), $fibo[-2] + modword($word));
#  print "\t($word $fibo[0] $fibo[1])\n";

  }

print "\n\n\n";