最終更新: 2019-01-15T14:13+0900
解けなくて飛ばした問題の中で一番最初の問題に再チ
普通に手続き的に書けば一瞬で答えが出る問題だ
#!rubyw # coding: utf-8 h = {} (2..100).each{|b| (2..100).inject(b){|_,| _ *= b h[_] = _ } } p h.size
最終更新: 2019-01-16T18:40+0900
解けなくて飛ばした問題の中で一番最初の問題に再チ
(そういえば以前も何度となく同じことを書いていたなと思い出しながら)泥臭く手を動かしただけ。
#!rubyw # coding: utf-8 Digits = *1..9 found = {} (1..2).each{|_| Digits.combination(_){|l_cmb| l_cmb.permutation{|l| l = l.join('').to_i Digits.combination(5-_){|r_cmb| r_cmb.permutation{|r| r = r.join('').to_i p = l * r found[p] = "#{l} * #{r} = #{p}" if /^(?:([1-9])(?!.*\1)){9}$/ =~ "#{l}#{r}#{p}" } } } } } p found.keys.inject(&:+)
最終更新: 2019-01-15T16:36+0900
解けなくて飛ばした問題の中で一番最初の問題に再チ
ただ手を動かしただけ。
#!rubyw # coding: utf-8 require 'mathn' found = [] (1..9).each{|numer| (1..9).each{|denom| frac = numer / denom (numer+1..9).each{|cancel／| found.push("#{numer}#{cancel／}/#{cancel／}#{denom}") if frac == (numer*10 + cancel／) / (cancel／*10 + denom) (1..denom-1).each{|cancel＼| found.push("#{cancel＼}#{numer}/#{denom}#{cancel＼}") if frac == (cancel＼*10 + numer) / (denom*10 + cancel＼) }} }} p found p found.map(&:to_r).inject(&:*).denominator
最終更新: 2019-01-15T17:32+0900
解けなくて飛ばした問題の中で一番最初の問題に再チ
以前は require 'prime' を避けてた気がするけど、今回は使
#!rubyw # coding: utf-8 require 'prime' require 'set' primes = Prime.each(1_000_000).to_set primes = primes.select{|p| s = "#{p}#{p}" l = s.length/2 (1..l-1).all?{|i| primes.include? s[i, l].to_i(10) } } p primes p primes.size
最終更新: 2019-01-15T21:09+0900
解けなくて飛ばした問題の中で一番最初の問題に再チ
例によ
#!rubyw # coding: utf-8 PalindromeGen = lambda{|digits| return Enumerator.new{|y| _next = lambda{|a| return digits.map{|_| a.map{|p10| "#{_}#{p10}#{_}" } }.flatten } odd = *digits even = digits.zip(digits).map{|_| _.join('') } yielder = lambda{|p| y << p} loop { odd = _next[odd.each(&yielder)] even = _next[even.each(&yielder)] } } } p10gen = PalindromeNGen["0".."9"] p2gen = PalindromeNGen["0".."1"] found = {} loop { p10 = p10gen.next.to_i(10) break if 1_000_000 < p10 p2gen.next while p2gen.peek.to_i(2) < p10 found[p10] = p10 if p2gen.peek.to_i(2) == p10 } p found.keys.map{|_| [_.to_s(10), _.to_s(2)] } p found.keys.inject(&:+)
最終更新: 2019-01-15T23:54+0900
解けなくて飛ばした問題の中で一番最初の問題に再チ
手を動かしただけ。
#!rubyw # coding: utf-8 require 'prime' require 'set' primes = Set.new found = {} Prime.each{|p| p = p.to_s(10) primes << p next if p.length == 1 next unless (1..(p.length-1)).all?{|w| primes.include? p[0,w] } next unless (1..(p.length-1)).all?{|i| primes.include? p[i,p.length-i] } p found[p] = p break if found.size == 11 } p found.keys.map(&:to_i).inject(&:+)
最終更新: 2019-01-16T18:01+0900
解けなくて飛ばした問題の中で一番最初の問題に再チ
手を動かしただけ。
#!rubyw # coding: utf-8 found = {} i = 1 9.downto(2){|n| loop { s = (1..n).map{|_| _*i }.join('') break if 9 < s.length i += 1 next if s.length < 9 next if s.index "0" found[s.to_i] = [i-1, 1..n] unless /(.).*\1/ =~ s } } p found p found.keys.sort.reverse
最終更新: 2019-01-16T00:54+0900
解けなくて飛ばした問題の中で一番最初の問題に再チ
素数
#!rubyw # coding: utf-8 require 'prime' found = ("1".."9").map{|n| ("1"..n).to_a.permutation.map{|_| _.join('').to_i }.select(&:prime?) }.flatten p found.sort.reverse
最終更新: 2019-01-16T03:47+0900
面倒くさくて飛ばした問題にチ
poker.txt の内容は本当にランダムなのか３番目までの高い役が１個も入
#!rubyw # coding: utf-8 Order = "23456789TJQKA" flush = lambda{|cards| # p ["flush", cards] if (cards.match(/^ .(.)(?: .\1){4}/)||[])[1] (cards.match(/^ .(.)(?: .\1){4}/)||[])[1] } straight = lambda{|cards| # p ["straignt", cards] if cards.scan(/ (.)/).map{|_,| Order.index _ }.sort.tap{|_| break _ == (_[0].._[0]+4).to_a ? Order[0] : nil } cards.scan(/ (.)/).map{|_,| Order.index _ }.sort.tap{|_| break _ == (_[0].._[0]+4).to_a ? Order[0] : nil } } four = lambda{|cards| p ["four", cards] if cards.scan(/ (.)/).sort.join('').scan(/(.)\1{3}/).map{|_,| _ }[0] cards.scan(/ (.)/).sort.join('').scan(/(.)\1{3}/).map{|_,| _ }[0] } three = lambda{|cards| # p ["three", cards] if cards.scan(/ (.)/).sort.join('').scan(/(.)\1{2}/).map{|_,| _ }[0] cards.scan(/ (.)/).sort.join('').scan(/(.)\1{2}/).map{|_,| _ }[0] } pairs = lambda{|cards| # p ["pairs", cards] unless cards.scan(/ (.)/).sort_by{|_,| - Order.index(_) }.join('').scan(/(.)\1/).map{|_,| _ }.empty? cards.scan(/ (.)/).sort_by{|_,| - Order.index(_) }.join('').scan(/(.)\1/).map{|_,| _ } } highcards = lambda{|cards| # p ["highcards", cards] cards.scan(/ (.)/).sort.join('').gsub(/(.)\1+/, '').split(//).sort_by{|_| - Order.index(_) } } fullhouse = lambda{|cards| # p ["fullhouse", cards] if pairs[cards].length == 2 and three[cards] pairs[cards].length == 2 and three[cards] } straightflush = lambda{|cards| suit = flush[cards] first = straight[cards] p ["straightflush", cards] if suit and first suit and first } royalflush = lambda{|cards| first = straightflush[cards] p ["royalflush", cards] if first and first == 'T' first and first == 'T' } compare = lambda{|h| h.map{|_| Array(_).map{|_| _ ? Order.index(_)||-1 : -2 } }.tap{|h| break h.first.length != h.last.length ? h.first.length <=> h.last.length : h.first <=> h.last } } contest = lambda{|c| [royalflush, straightflush, four, fullhouse, flush, straight, three, pairs, highcards ].each{|ranktest| h = c.map(&ranktest) return compare[h] if h.any?{|_| _ and not _.empty? } } raise "no contest" } p DATA.lines.map{|ln| p1 = " " + ln[0, 15] p2 = ln[14, 15] + " " contest[[p1, p2]] }.count(1) __END__ content of poker.txt here.
最終更新: 2019-01-14T23:35+0900
解けなくて飛ばした問題の中で一番最初の問題に再チ
#!rubyw # coding: utf-8 require 'prime' a = *-1000..0 b = Prime.each(1000).reject {|_| _ < 80 } remains = a.product b (0..1000).each {|n| remains.reject! {|a, b| n == b or n + a == -b or (n * (n + a) + b) <= 0 or not (n * (n + a) + b).prime? } puts "remains #{remains.size}" puts "a = %d; b = %d; n = %d" % [*remains[0], n] if remains.size == 1 break if remains.size <= 1 }