#!/usr/bin/perl -w

use strict;
my ($stage) = (0);

# $stage==0: 還在尋找想要的段落; $stage==1: 正在列印想要的段落

while (<STDIN>) {
    if ($stage == 0) {
	next unless /^###\s*$ARGV[0]\s*###/;
	print;
	$stage = 1;
    } elsif ($stage == 1) {
	last if /^###\s*\w+\s*###/;
	print;
    }
}