Module: AtCoderFriends::Parser::Constraints

Defined in:
lib/at_coder_friends/parser/constraints.rb

Overview

parses constraints

Constant Summary collapse

SECTIONS = 
[
  Problem::SECTION_CONSTRAINTS,
  Problem::SECTION_IN_FMT,
  Problem::SECTION_IO_FMT,
  Problem::SECTION_STATEMENT
].freeze
NAME_PAT = 
/[0-9a-z_{},]+/i.freeze
NAMES_PAT = 
/#{NAME_PAT}(?:\s*,\s*#{NAME_PAT})*/.freeze
NUM_PAT = 
/[-+*^0-9{}, ]+/.freeze
MAX_PATTERN = 
/
  (?:
    (#{NAMES_PAT})\s*<\s*(#{NUM_PAT})
    |(#{NAMES_PAT})\s*は\s*#{NUM_PAT}\s*以上\s*(#{NUM_PAT})\s*以下の整数
  )
/xmi.freeze

Class Method Summary collapse

Class Method Details

.normalize_content(s) ⇒ Object 



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# File 'lib/at_coder_friends/parser/constraints.rb', line 47

def normalize_content(s)
  # 1) &npsp; , fill-width space -> half width space
  # 2) {i, j}->{i,j} {N-1}->{N} shortest match
  s
    .tr('０-９Ａ-Ｚａ-ｚ', '0-9A-Za-z')
    .gsub(/[[:space:]]/) { |c| c.gsub(/[^\t\n]/, ' ') } # 1)
    .gsub(%r{</?var>}i, "\t")
    .gsub(%r{<sup>([^<>]+)</sup>}i, '^\1')
    .gsub(%r{<sub>([^<>]+)</sub>}i, '_{\1}')
    .gsub(/<("[^"]*"|'[^']*'|[^'"<>])*>/, '')
    .gsub('&amp;', '&')
    .gsub(/(＜|≦|≤|&lt;|&leq?;|\\lt|\\leq?q?)/i, '<')
    .gsub('\\ ', ' ')
    .gsub('\\,', ',')
    .gsub('\\|', '|')
    .gsub('，', ', ')
    .gsub('×', '*')
    .gsub('\\lvert', '|')
    .gsub('\\rvert', '|')
    .gsub('\\mathit', '')
    .gsub('\\mathrm', '')
    .gsub('\\times', '*')
    .gsub(/\\begin(\{[^{}]*\})*/, '')
    .gsub(/\\end(\{[^{}]*\})*/, '')
    .gsub(/\{\}/, ' ')
    .gsub('|', '')
    .gsub(/\{.*?\}/) { |w| w.delete(' ()').gsub(/{(.+)-1}\z/, '\1') } # 2)
end

.normalize_names(s) ⇒ Object 



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# File 'lib/at_coder_friends/parser/constraints.rb', line 76

def normalize_names(s)
  # 1) {i,j}->{ij} shortest match
  s
    .gsub(/\{.*?\}/) { |w| w.delete(',') } # 1)
    .delete('{}')
    .gsub(/\s+/, '')
    .split(',')
    .reject(&:empty?)
end

.normalize_value(s) ⇒ Object 



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# File 'lib/at_coder_friends/parser/constraints.rb', line 86

def normalize_value(s)
  s
    .split(', ')
    &.map do |v|
      v
        .delete(' {}')
        .gsub(/\A[+*^,]+/, '') # remove preceding symbols
        .gsub(/[+*^,]+\z/, '') # remove trailing symbols
    end
    &.reject(&:empty?)
    &.first
end

.parse(str) ⇒ Object 



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# File 'lib/at_coder_friends/parser/constraints.rb', line 35

def parse(str)
  str = normalize_content(str)
  pats = str.scan(MAX_PATTERN).map(&:compact)
  pairs = pats.each_with_object([]) do |(k, v), result|
    value = normalize_value(v)
    next unless value && !value.empty?

    normalize_names(k).each { |name| result << [name, value] }
  end
  pairs.uniq.map { |k, v| Problem::Constant.new(k, :max, v) }
end

.process(pbm) ⇒ Object 



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# File 'lib/at_coder_friends/parser/constraints.rb', line 25

def process(pbm)
  maxs = []
  SECTIONS.any? do |section|
    next unless (text = pbm.sections[section]&.html)

    !(maxs = parse(text)).empty?
  end
  pbm.constants += maxs
end