あんまり書いてないな

　最近仕事ではPHPばかりなのでRubyを使っていないのでACM/ICPC国内予選突破の手引きの問題をRubyでといてみる。

Hanafuda Shuffle

　Array#[start, length]で一発で解ける件について

# 1978
# hanafuda shuffle

def shuffle(n,r)
  deck = (1..n).to_a.reverse
  r.times do
    p, c = STDIN.readline.split(' ').map {|n| n.to_i }
    pth = deck[0, p - 1]
    cth = deck[p-1,c]
    deck[0,c] = cth
    deck[c,p-1] = pth
  end
  deck[0]
end

def hanafuda_shuffle
  results = []
  loop do
    n, r = STDIN.readline.split(' ').map {|n| n.to_i }
    return results if n == 0 and r == 0
    results << shuffle(n, r)
  end
end

puts hanafuda_shuffle.join("\n")

Ohgas' Fortune

　総当りで最高のものを抽出。
　ぜんぜんオブジェクト指向のプログラムじゃない。。。プログラマに向いていないんじゃないかと思える。。

# 2683
# ohgas' fortune

require 'pp'

class Operation
  def initialize(interest, rate, charge)
    @interest = interest
    @rate = rate
    @charge = charge
  end
  attr_reader :rate
  attr_reader :charge

  def simple?
    @interest == 0
  end
  def compound?
    @interest == 1
  end
end

def search_best_operation
  fund = STDIN.readline.to_i
  years = STDIN.readline.to_i
  operations = []
  n = STDIN.readline.to_i
  n.times do
    i, r, c = STDIN.readline.split(' ')
    operations << Operation.new(i.to_i, r.to_f, c.to_i)
  end
  search(fund, years, operations)
end

def search(fund, years, operations)
  operations.map do |operation|
    calc(fund, years - 1, operations, operation, 0)
  end.max
end

def calc(fund, years, operations, operation, acc_interest)
  interest = (fund * operation.rate).to_i
  acc_interest += interest if operation.simple?
  fund += interest if operation.compound?
  fund -= operation.charge
  return fund + acc_interest if years == 0
  operations.map do |operation|
    calc(fund, years - 1, operations, operation, acc_interest)
  end.max
end

def main
  results = []
  STDIN.readline.to_i.times do
    results << search_best_operation
  end
  puts results.join("\n")
end

main

keitai message

#
# keitai message

class Button
  def initialize(table)
    @table = table
    reset
  end

  def reset
    @index = -1
  end

  def push
    @index += 1
  end

  def peek
    @table[@index % @table.size]
  end

  def pop
    p = peek
    reset
    p
  end
end

class Keitai
  def initialize
    @buttons = [
      nil,
      Button.new(['.', ',', '!', '?', ' ']),
      Button.new(['a', 'b', 'c']),
      Button.new(['d', 'e', 'f']),
      Button.new(['g', 'h', 'i']),
      Button.new(['j', 'k', 'l']),
      Button.new(['m', 'n', 'o']),
      Button.new(['p', 'q', 'r', 's']),
      Button.new(['t', 'u', 'v']),
      Button.new(['w', 'x', 'y', 'z']),
    ]
    @buffer = ''
    @target = nil
  end

  def push(n)
    if n == 0
      return if @target == nil
      @buffer << @target.pop
      @target = nil
      return
    end
    if @target == nil
      @target = @buttons[n]
    end
    @target.push
  end

  def to_s
    @buffer
  end
end

def main
  results = []
  STDIN.readline.to_i.times do
    keitai = Keitai.new
    STDIN.readline.split(//).map {|n| n.to_i}.each {|n| keitai.push n }
    results << keitai.to_s
  end
  puts results.join("\n")
end

main