DZone Snippets: Wancw's Code Snippets

Show Stars - Loop Version

WanCW (WanCW) — Wed, 25 Jun 2008 06:56:09 GMT

題目 http://www.mobile01.com/topicdetail.php?f=300&t=415016&m=f&r=4&last=6753118#11



#include 



int main (int argc, char* argv[])

{

        int N, total_line, spl, l, n;

        scanf ("%d", &N);

        total_line = N; // 第二題要把 N 改成 (N << 1) - 1;



        for (spl = 1, l = 0, n = 0; l < total_line; )

        {

                putchar ('*');

                ++n;

                if (n>=spl)

                {

                        putchar ('\n');

                        ++l;

                        spl += (l                        n = 0;

                }

        }

        return 0;

}

Show Stars - Recursive Version

WanCW (WanCW) — Wed, 25 Jun 2008 06:52:33 GMT

題目 http://www.mobile01.com/topicdetail.php?f=300&t=415016&m=f&r=4&last=6753118#11



#include 



void show_star (n)

{

        if (n == 0)

                putchar('\n');

        else

        {

                putchar ('*');

                show_star(n-1);

        }

}



void show_line (int from, int to, int step)

{

        show_star (from);

        if (from != to)

                show_line (from+step, to, step);

}



int main (int argc, char* argv[])

{

        int N;

        scanf ("%d", &N);

        show_line(1, N, 1);

        /* 加上下面這行就是第二題 */

        /* show_line(N-1, 1, -1); */

        return 0;

}

Include javascript by DOM

WanCW (WanCW) — Tue, 31 Jul 2007 13:55:45 GMT

Orignial: http://www.codepost.org/browse/snippets/85



function include(file)

{

      var script  = document.createElement('script');

      script.src  = file;

      script.type = 'text/javascript';



      document.getElementsByTagName('head').item(0).appendChild(script);

}

Include javascript by XMLHttpRequest

WanCW (WanCW) — Tue, 31 Jul 2007 13:51:25 GMT

Original from http://www.exit12.org/archives/12



function include(jsFileLocation)

{

	if(window.XMLHttpRequest)

	{

		var req = new XMLHttpRequest();

	}

	else

	{

		var req = new ActiveXObject("Microsoft.XMLHTTP");

	}

	req.open("GET", jsFileLocation,false);

	req.onreadystatechange = function()

	{

		if (req.readyState == 4)

		{

			window.eval(req.responseText);

		}

	}

	req.send(null);

}

Multiple Rails Applications with lighttpd

WanCW (WanCW) — Tue, 03 Apr 2007 03:32:07 GMT



# lighttpd.conf

$HTTP["url"] =~ "^/base_url_to_app1/" {

  server.document-root = "/path/to/app1/public/"

  alias.url = ( "/base_url_to_app1/" => "/path/to/app1/public/" )

  server.error-handler-404 = "/base_url_to_app1/dispatch.fcgi"

  fastcgi.server = (

    ".fcgi" => ( (

      "socket" => "/tmp/app1.socket",

      "bin-path" =>  "/path/to/app1/public/dispatch.fcgi",

    ) )

  )

}



$HTTP["url"] =~ "^/base_url_to_app2/" {

  # ...

}



# config/environment.rb

module ActionController

  class AbstractRequest

    alias_method :orig_rel_url_root, :relative_url_root

    def relative_url_root

      if (@env['SCRIPT_NAME'] && /\/dispatch\.(fcgi|rb|cgi)$/ =~ @env['SCRIPT_NAME'])

        @env["SCRIPT_NAME"].to_s.sub(/\/dispatch\.(fcgi|rb|cgi)$/, '')

      else

        orig_rel_url_root

      end

    end

  end

end

General Delimited Input in Ruby

WanCW (WanCW) — Mon, 06 Nov 2006 22:52:35 GMT

In ruby there are several special literal notations:



%{blah}       # or %Q{blah} # same as "blah" but igornes " and '

%q{blah}      # same as 'blah' but no interpolation

%w{blah blah} # same as "blah blah".split

%r{blah}      # same as /blah/

%x{ls}        # same as `ls`

Overload for Ruby

WanCW (WanCW) — Fri, 22 Sep 2006 13:49:58 GMT

An module let you overload functions



# Example:

#

# class Test1

#   include Overload

# 

#   def foo

#     puts "foo # Original one"

#   end

# 

#   overload :foo, :foo_str, String do |str, x|

#     puts "foo_str(String str, x)"

#   end

# 

#   overload :foo, Integer do |i|

#     puts "foo(Integer i) # no specific name"

#   end

# end

module Overload



  def self.included(klass)

    class << klass

      include Overload::Feature

    end

  end



  def self.spec_to_cond(spec)

    code = "args.length == #{spec[0]}"

    spec[1..-1].each_with_index { |s, i|

      code << " && #{s.inspect} === args[#{i}]"

    }

    code

  end



  module Feature



    private



    def overload(method_id, *spec, &block)

      if spec[0].instance_of? Symbol

        specific_method_id = spec.shift

        define_method(specific_method_id, block) if block

        block = instance_method(specific_method_id)

      elsif block

        define_method(method_id, block)

        block = instance_method(method_id)

        remove_method(method_id)

      else

        raise "You must give a block or a name of existing method!"

      end



      spec.unshift(block.arity)

      add_method_to_dispatch_table(method_id, spec, block)



      update_dispatcher(method_id)

    end



    def add_method_to_dispatch_table(method_id, key, block)

      if !dispatch_table[method_id]

        dispatch_table[method_id] = Hash.new

      end

      dispatch_table[method_id][key] = block

    end



    def update_dispatcher(method_id)

      remove_method(method_id) if method_defined?(method_id)

      class_eval dispatcher_code(method_id), "#{method_id}_dispatcher", 0

    end



    def dispatcher_code(method_id)

      method_body = <<-EOS

        def #{method_id.to_s}(*args, &blk)

          dt = DispatchTable[#{method_id.inspect}]

      EOS



      sorted_dispatch_table_of(method_id).each_with_index do |(spec, block), i|

        method_body << <<-EOS

          #{(i==0) ? "if" : "elsif"} #{Overload::spec_to_cond(spec)}

            dt[#{spec.inspect}].bind(self).call(*args, &blk)

        EOS

      end



      method_body << <<-EOS

          else

            raise "Couldn't find method for #{method_id}(\#{args.inspect[1..-2]})"

          end

        end

      EOS

    end



    def sorted_dispatch_table_of(method_id)

      dispatch_table[method_id].sort do |a,b|

        a[0].length <=> b[0].length

      end

    end



    def dispatch_table

      const_set("DispatchTable", Hash.new) if !const_defined?("DispatchTable")

      const_get("DispatchTable")

    end



  end



end