DouKaku?beta

Language detail: Perl

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π (Nested Flatten) 
ビジュアル的にはこっちのほうがおもしろい
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use strict;
use warnings;

use bignum;

use Memoize;

sub fract
{
  my $n = shift;
  $n == 0 || $n == 1 ? 1 :
  $n * fract($n-1);
}
sub f
{
  my $n = shift;
  $n < 0 ? 0 :
  fract(2 * $n) /
  ((2 ** (4 * $n + 1)) * (fract($n) ** 2) * (2 * $n + 1)) +
  f($n-1);
}
memoize(q/fract/);
memoize(q/f/);

my $N = 1024;

print "@{[6 * f($_)]}\n" for 1 .. $N;

とりあえず、参考ページにあった数式で素直に計算。
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use strict;
use warnings;

use bignum;

use List::Util qw/reduce/;
use Memoize;

sub fract
{
  $_[0] == 0 || $_[0] == 1 ? 1 :
  $_[0] * fract($_[0]-1);
}
memoize(q/fract/);

my $N = 32;

print 6 * reduce {
  no warnings qw/once/;
  $a + $b
} map {
  fract(2 * $_) /
  ((2 ** (4 * $_ + 1)) * (fract($_) ** 2) * (2 * $_ + 1))
} 0 .. $N;
タブ区切りデータの処理 (Nested Flatten) 
標準入力から読込
標準出力への出力

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@header = split(/\t/, <>);
($header[2], $header[1]) = ($header[1], $header[2]);
print join("\t", @header);

print map { ($_->[2], $_->[1])=($_->[1], $_->[2]);$_->[3]++; join("\t", @$_)."\n"; } sort{ $a->[0] <=> $b->[0] } map [split /\t/], <> ;
数値リストの圧縮 (Nested Flatten)

#7713 をperlに移植した感じになりました。

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use strict;
use warnings;

my @list = (1, 3, 4, 5, 6, 12, 13, 15, 20, 25, 26, 27);

my $prevd = $list[0];
my @result = ([+$list[0]]);
for (my $idx = 1; $idx < @list; ++$idx) {
    my $d = $list[$idx] - $list[$idx - 1];

    if ( $prevd && $prevd != $d ) {
        push @result, [$list[$idx]];
        $prevd = 0;
    }
    else {
        push @{$result[$#result]}, $list[$idx];
        $prevd = $d;
    }
}

@result =
map {
    if ( @$_ > 2 ) {
        my $d = $_->[1] - $_->[0];
        [@$_[0, $#$_], ($d>1)?($d):()];
    }
    else {
        @$_;
    }
} @result;

use Data::Dumper;
print Dumper(\@result);
2^i * 3^j * 5^k なる整数 (Nested Flatten) 
one-linerというかgolfというか...
アルゴリズムは他の皆さんと同じです。
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1==shift@z&&++$n&&printf"%d = 2^%d * 3^%d *%s 5^%d\n",@z
while$n<100&&(@z=(++$i,$i,0,0,'',0))&&
map{$z[0]/=$_,++$z[$_]until$z[0]%$_}2,3,5
比較しないソートの作成 (Nested Flatten) 
バケットソートです。ワンライナーで書いてみました。
最大値と個数は無視します。
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($n,$x,$c,@s)=@ARGV;$b[$_-$n]++for@s;$b[$_]&&print(($_+$n.' ')x$b[$_])for 0..$#b
起動オプションの解析 (Nested Flatten) 
-d は、必須オプションとして処理しています。
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use strict;
use Getopt::Std;

#ex>cmdopt -o [-q] -d{0|1|2} 文字列 [文字列 ...]

our( $opt_o, $opt_q, $opt_d );

getopts('oqd:');

die "oオプションが指定されていない\n" unless $opt_o;
die "dオプションが指定されていない\n" unless defined $opt_d;
die "dオプションの引数は0-2\n" unless ($opt_d eq '0' || $opt_d eq '1' || $opt_d eq '2');
die "パラメータが指定されていない\n" unless @ARGV;

print "[オプション情報]\n";
print "o(output): ON\n" if $opt_o; 
print "q(quote): " . ($opt_q ? "ON" : "OFF") . "\n"; 
print "d(debug): $opt_d\n";

print "\n[パラメータ情報]\n";
printf("指定数: %d\n", $#ARGV+1);

my $c = 0;
for my $arg (@ARGV){
    $c++;
    print "$c: $arg\n";
}
マルバツゲーム：賢いプレイヤー (Nested Flatten) 
4つの戦略(どのように石を置くか)を作りました：
  1. put_stone_random ... ランダムに置く。
  2. ps_prevent_losing ... リーチをかけられてるなら、防ぐ。さもなくば1.の戦略をとる。
  3. ps_grasp_chance ...リーチをかけてるなら、そこにおいてゲームに勝つ。さもなくば2.の戦略をとる。
  4. ps_smart ...
    リーチをかけてるなら、そこにおいてゲームに勝つ。
    リーチをかけられてるなら、防ぐ。
    さもなくば、可能な限り、ダブルリーチを仕掛けに行く。

ps_smart を書くために、マルバツゲームを手で解きました。
各盤面に対する最善手を %ptn_pos_h に押し込めました。
蛇足：%ptn_pos_h を調整することで、 ps_smart の強さを調整できます。

実行結果： perl marubatsu.pl
***** ps_smart vs put_stone_random *****
game 1..10000
D=>115 o=>9885 
***** put_stone_random vs ps_smart *****
game 10001..20000
D=>2373 x=>7627 
***** ps_smart vs ps_smart *****
game 20001..20100
D=>100 

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$board = [map {[map {'-'} 0..2]} 0..2];

sub game {
    clear($board);
    game_loop(@_);
}
sub game_loop {
    my ($player1, $player2) = @_;
    my $w;
    $player1->{put_stone}($player1->{stone});
    if ($w=check($board)) { return $w; }
    game_loop($player2,$player1);
}

sub put_stone_random {
    my $stone = shift;
    while (1) {
    my($r,$c) = (int rand @$board, int rand @$board);
    if (0<=$r and $r<@$board and
        0<=$c and $c<@$board and
        $board->[$r][$c] eq '-') {
        $board->[$r][$c] = $stone;
        last;
    }
    }
}
sub ps_prevent_losing { # ps :abbrev: put_stone
    my $stone = shift;
    my($r,$c) = pos_oppreach($board,$stone);
    if (defined($r) and defined($c)) {
    $board->[$r][$c] = $stone;
    } else {
    put_stone_random($stone);
    }
}
sub ps_grasp_chance {
    my $stone = shift;
    my($r,$c) = pos_oppreach($board,oppstone($stone));
    if (defined($r) and defined($c)) {
    $board->[$r][$c] = $stone;
    } else {
    ps_prevent_losing($stone);
    }
}
sub ps_smart {
    my $stone = shift;
    # ps_grasp_chance
    my($r,$c) = pos_oppreach($board,oppstone($stone));
    if (defined($r) and defined($c)) {
    $board->[$r][$c] = $stone;
    return;
    }
    # ps_prevent_losing
    ($r,$c) = pos_oppreach($board,$stone);
    if (defined($r) and defined($c)) {
    ps_prevent_losing($stone);
    return;
    }
    # attack dreach # dreach :abbrev: double reach
    ($r,$c) = pos_smart($board,$stone);
    if (defined($r) and defined($c)) {
    $board->[$r][$c] = $stone;
    return;
    }
    put_stone_random($stone);
}

sub pos_oppreach {
    my($board,$stone) = @_;
    my($r,$c);
    ($r,$c) = pos_oppreach_row($board,$stone);
    if (defined($r) and defined($c)) { return ($r,$c); }
    ($r,$c) = pos_oppreach_column($board,$stone);
    if (defined($r) and defined($c)) { return ($r,$c); }
    ($r,$c) = pos_oppreach_crossline($board,$stone);
    if (defined($r) and defined($c)) { return ($r,$c); }
    (undef, undef)
}
sub pos_oppreach_row {
    my($board,$stone) = @_;
    my @board_strs = join0s($board);
    for (0..(@$board-1)) {
    my $i = index_oppreach($board_strs[$_], $stone);
    if (defined($i)) {
        return ($_, $i);
    }
    }
    (undef, undef);
}
sub pos_oppreach_column {
    my($board,$stone) = @_;
    my @board_strs = ($board->[0][0].$board->[1][0].$board->[2][0],
              $board->[0][1].$board->[1][1].$board->[2][1],
              $board->[0][2].$board->[1][2].$board->[2][2]);
    for (0..(@$board-1)) {
    my $i = index_oppreach($board_strs[$_], $stone);
    if (defined($i)) {
        return ($i, $_);
    }
    }
    (undef, undef);
}
sub pos_oppreach_crossline {
    my($board,$stone) = @_;
    my @board_strs = get_crosslines($board);
    my $i = index_oppreach($board_strs[0], $stone);
    if (defined($i)) {
    return ($i,$i);
    }
    $i = index_oppreach($board_strs[1], $stone);
    if (defined($i)) {
    return (@$board-1-$i,$i);
    }
    (undef, undef);
}
sub index_oppreach { # test: index_oppreach('o-o', 'x') == 1
    my $s = $_[0];
    my $o = oppstone($_[1]);
    if ($o eq 'o') {
        if ($s eq '-oo') { return 0; }
        if ($s eq 'o-o') { return 1; }
        if ($s eq 'oo-') { return 2; }
    } else { # $o eq 'o'
        if ($s eq '-xx') { return 0; }
        if ($s eq 'x-x') { return 1; }
        if ($s eq 'xx-') { return 2; }
    }
    undef;
}
sub oppstone {
    $_[0] eq 'o' ? 'x' : $_[0] eq 'x' ? 'o' : undef;
}

my %ptn_pos_h;
{
    my $ptn_pos_href = {
    # play first
    '--- --- ---' => [0,0],
    'ox- --- ---' => [1,1], # [2,0] is also ok : [2,0] [1,0] [2,2]
    'ox- -o- --x' => [1,0], # dreach
    'o-x --- ---' => [2,0],
    'o-x x-- o--' => [2,2], # dreach
    'o-- --x ---' => [2,0], # dreach by gc
    'o-- --- --x' => [2,0],
    'o-- x-- o-x' => [0,2], # dreach ... same as 'o-x x-- o--'
    'o-- -x- ---' => [2,2],
    'o-x -x- --o' => [2,0], # dreach
    
       # play second / first ps pos == (0 0)
    'o-- --- ---' => [1,1],
    'o-- -x- --o' => [2,1], # draw by gc
    'o-- -x- -o-' => [2,2], # dreach by gc 1/5 , draw by gc 4/5
       # play second / first ps pos == (1 1)    
    '--- -o- ---' => [0,0],
    'x-- -o- --o' => [0,2], # draw by gc
       # play second / first ps pos == (0 1)
    '-o- --- ---' => [0,0],
    'xoo --- ---' => [2,0],
    'xoo o-- x--' => [2,2], # dreach
    'xo- --o ---' => [2,0], # dreach by gc
    
    'xo- --- o--' => [1,1], # draw by gc
    
    'xo- o-- ---' => [2,1],
    'xoo o-- -x-' => [2,2], # dreach
    'xo- o-- ox-' => [0,2], # draw by gc
    'xo- o-- -xo' => [0,2], # draw by gc
    
    'xo- --- --o' => [1,1], # dreach by gc 1/5 , draw by gc 4/5
    };
    %ptn_pos_h = %$ptn_pos_href;
}
sub pos_smart { # assume: play first => 'o', play second => 'x', marubatsuptn
    my($board,$stone) = @_;
    for my $m (0..1) { # means: nflip
    for my $n (0..3) { # means: nrot
        my $ptn = match_board(brott($n,bflipt($m,$board)));
        if (defined $ptn) {
        #print "$ptn => @{$ptn_pos_h{$ptn}} : $m $n : debugwrite";
        return to_a(pflipt($m,prott(-$n,$ptn_pos_h{$ptn})));
        }
    }
    }
    (undef, undef);
}
sub brott {
    my($n, $board) = @_;
    dotimes($n % 4, $board, \&brot);
}
sub bflipt {
    my($n, $board) = @_;
    dotimes($n % 2, $board, \&bflip);
}
sub pflipt {
    my($n, $pos) = @_;
    dotimes($n % 2, $pos, \&pflip);
}
sub prott {
    my($n, $pos) = @_;
    dotimes($n % 4, $pos, \&prot);
}
sub dotimes {
    my($n, $obj, $coderef) = @_;
    $n==0 ? $obj : dotimes($n-1, $coderef->($obj), $coderef);
}
sub brot {
    trans(bflip($_[0]));
}
sub bflip {
    [map {[reverse @$_];} @{$_[0]}];
}
sub pflip {
    my @b = @{$_[0]};
    $b[1] = 2 - $b[1]; # pos flip
    \@b;
}
sub prot {
    my @b = @{$_[0]};
    $b[0]-=1; $b[1]-=1;
    my @c = (-$b[1], $b[0]); # pos rot ... 90 degree
    $c[0]+=1; $c[1]+=1;
    \@c;
}
sub match_board {
  my $board_str = join(' ', join0s(shift));
  my @mp = grep { $board_str eq $_; } keys %ptn_pos_h;
  (scalar @mp) ? $mp[0] : undef;
}
sub to_a {
    @{$_[0]};
}

sub check {
    my @b = @{$_[0]};
    my $w;
    # check rows
    for my $r (0..2) {
    my $l = $b[$r]->[0]; # abbrev: left of board
    if ($l ne'-' and $l eq$b[$r]->[1] and $l eq$b[$r]->[2]) { return $l; }
    }
    # check columns
    for my $c (0..2) {
    my $t = $b[0]->[$c]; # abbrev: top of board
    if ($t ne'-' and $t eq$b[1]->[$c] and $t eq$b[2]->[$c]) { return $t; }
    }
    # check crosslines
    my $p = $b[0]->[0]; # abbrev: pos
    if ($p ne'-' and $p eq$b[1]->[1] and $p eq$b[2]->[2]) { return $p; }
    $p = $b[2]->[0];
    if ($p ne'-' and $p eq$b[1]->[1] and $p eq$b[0]->[2]) { return $p; }
    # check draw
    if (filledp(\@b)) { return 'D'; } # means: draw
    undef;
}

sub join0s {
    my @b = @{$_[0]};
    my @a;
    $a[0] = join '', @{$b[0]};
    $a[1] = join '', @{$b[1]};
    $a[2] = join '', @{$b[2]};
    @a;
    # map {join '', @$_} @{$_[0]};
}
sub trans {
    my $m = shift;
    my $n = [];
    for my $r (0..2) {
    for my $c (0..2) {
        $n->[$c][$r] = $m->[$r][$c];
    }
    }
    $n;
}
sub get_crosslines {
    my $b = shift;
    join0s [[map {$b->[      $_][$_]} 0..(@$b-1)],
        [map {$b->[@$b-1-$_][$_]} 0..(@$b-1)]];
}
sub filledp {
    my $b = shift;
    for my $r (0..(@$b-1)) {
    for my $c (0..(@{$b->[$r]}-1)) {
        if ($b->[$r][$c] eq '-') { return 0; }
    }
    }
    1;
}

# utilities
sub clear {
    my $b = shift;
    for my $r (0..(@$b-1)) {
    for my $c (0..(@{$b->[$r]}-1)) {
        $b->[$r][$c] = '-';
    }
    }
}

################### run game ###################

$gc = 0; # abbrev: game count

sub game_times {
    my($player1,$player2,$ngame) = @_;
    my %wc;
    print "***** $player1 vs $player2 *****\n";
    print "game ", $gc+1, "..", $gc+$ngame, "\n";
    $gc += $ngame;
    for (1..$ngame) {
    my $w = game({put_stone=>\&$player1, stone=>'o'},
             {put_stone=>\&$player2, stone=>'x'});
    $wc{$w}++;
    }
    while (my($k,$v) = each(%wc)) {
    print "$k=>$v ";
    }
    print "\n";    
}

$ngame = 10000;
game_times('ps_smart', 'put_stone_random', $ngame);
game_times('put_stone_random', 'ps_smart', $ngame);
game_times('ps_smart', 'ps_smart', 100);
LL Golf Hole 9 - トラックバックを打つ (Nested Flatten) 
お題がGolf向けじゃないとか..

後、さすがに一行では表示がえらいことになるので、適当に改行
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use LWP::UserAgent;
print LWP::UserAgent->new->post(
  'http://ll.jus.or.jp/2008/blog/archives/38/trackback',
  {qw{blog_name LLGolfHole9 title llfuture url http://ja.doukaku.org/207
    excerpt LLGolf最終ホールを打ってみた}})->content
文字列型日時ののN秒後時間取得 (Nested Flatten)

モジュールなしで書いた

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#! /usr/bin/perl
use strict;
use warnings;

my $date_string = 20080827235925;
my $add_seconds = 40;

print DateEx($date_string,$add_seconds);

sub DateEx{
    my ($date_string, $add_seconds) = @_;
    
    return 'Error!' unless $date_string =~ /^\d{14}$/;
    return 'Error!' unless $add_seconds =~ /^-?\d+$/;
    
    my ($year,$month,$day,$hour,$minutes,$seconds)
        = $date_string =~ /^(\d{1,4})(\d{2})(\d{2})(\d{2})(\d{2})(\d{2})$/;
    my @result = add_seconds($year,$month,$day,$hour,$minutes,$seconds,$add_seconds);
    
    return sprintf("%04d%02d%02d%02d%02d%02d",@result);
}

sub add_seconds{
    my ($year,$month,$day,$hour,$minutes,$seconds,$add_seconds) = @_;
    
    #時間、秒を先に出す
    my ($tmp_day,$result_hour,$result_minutes,$result_seconds)
        = seconds_to_day($add_seconds + day_to_seconds($day-1,$hour,$minutes,$seconds));
    
    #日付を計算
    my ($result_year, $result_month, $result_day)
        = date_add($year,$month,$tmp_day);
    
    return ($result_year,$result_month,$result_day,$result_hour,$result_minutes,$result_seconds);
}

sub day_to_seconds{#何日、何時間、何分の形式を総秒数に変換
    my ($day,$hour,$minutes,$seconds) = @_;
    
    my $SECONDS_PER_MINUTES = 60;
    my $SECONDS_PER_HOUR = $SECONDS_PER_MINUTES * 60;
    my $SECONDS_PER_DAY = $SECONDS_PER_HOUR * 24;
    
    my $total_second = $day     * $SECONDS_PER_DAY
                     + $hour    * $SECONDS_PER_HOUR
                     + $minutes * $SECONDS_PER_MINUTES
                     + $seconds
                     ;
    return $total_second;
}

sub seconds_to_day{#秒数を　何日、何時間、何分の形式に変換
    my ($total_seconds) = @_;
    
    my $SECONDS_PER_MINUTES = 60;
    my $SECONDS_PER_HOUR = $SECONDS_PER_MINUTES * 60;
    my $SECONDS_PER_DAY = $SECONDS_PER_HOUR * 24;
    
    my ($day,$hour,$minutes,$seconds) = (0,0,0,0);
    
    if($total_seconds > 0){
        $day = int($total_seconds / $SECONDS_PER_DAY) + 1;
        $hour = int($total_seconds / $SECONDS_PER_HOUR) % 24;
        $minutes = int($total_seconds / $SECONDS_PER_MINUTES) % 60;
        $seconds = $total_seconds % 60;
    }
    elsif($total_seconds < 0){
        $day = (int(($total_seconds * (-1))/$SECONDS_PER_DAY) + 1) * (-1);
        $total_seconds += $day * $SECONDS_PER_DAY * (-1);
        $hour = int($total_seconds / $SECONDS_PER_HOUR) % 24;
        $minutes = int($total_seconds / $SECONDS_PER_MINUTES) % 60;
        $seconds = $total_seconds % 60;
    }
    return ($day,$hour,$minutes,$seconds);
}

sub date_add{#2008年8月33日は2008年9月2日のような考え方
    my ($year,$month,$day) = @_;
    
    #400年以上のスパンがある場合
    while(abs($day) > (my $DAYS_IN_400YEARS = 365*400+97)){
        if($day > 0){
            $day -= $DAYS_IN_400YEARS;
            $year += 400;
        }
        else{
            $day += $DAYS_IN_400YEARS;
            $year -= 400;
        }
    }
    #1年以上のスパンがある場合
    while(abs($day) > 366){
        if($day > 0){
            if($month <= 2){
                while($day > 366){
                    _uru_or_not($year) ? $day -= 366 : $day -= 365;
                    $year++;
                }
            }
            else{
                while($day > 366){
                    _uru_or_not($year+1) ? $day -= 366 : $day -= 365;
                    $year++;
                }
            }
        }
        else{
            if($month <= 2){
                while($day < -366){
                    _uru_or_not($year-1) ? $day += 366 : $day += 365;
                    $year--
                }
            }
            else{
                while($day < -366){
                    _uru_or_not($year) ? $day += 366 : $day += 365;
                    $year--
                }
            }
        }
    }
    #一月づつ、足すもしくはさかのぼる
    while(!(($day > 0) && (_get_days_of_month($year,$month) >= $day))){
        if($day > 0){
            $day -= _get_days_of_month($year,$month);
            $month++;
            if($month == 13){
                $year++;
                $month = 1;
            }
        }
        else{
            $month--;
            if($month == 0){
                $year--;
                $month = 12;
            }
            $day += (_get_days_of_month($year,$month) + 1);
        }
    }
    return ($year,$month,$day);
}

sub _uru_or_not{#閏年か否かの判定
    my ($year) = @_;
    return 1 if($year % 400 == 0);
    return 0 if($year % 100 == 0);
    return 1 if($year % 4   == 0);
    return 0;
}

sub _get_days_of_month{#年と月を与えるとその日数を返す
    my ($year,$month) = @_;
    
    my @days_of_months = qw{0 31 28 31 30 31 30 31 31 30 31 30 31};
    if(($month == 2) && (_uru_or_not($year))){
        return 29;
    }
    return $days_of_months[$month];
}

Perlにまでパーサっがあったのですね。。。
僕が妥協した時はPOSIXを使ったべた書きでした。
# ほとんどCとかわりません(笑