Submission #169665

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Source Code Expand

#!/usr/bin/env ruby
@memo={}
def kai(n)
  (1..n).to_a.inject(1){|r, i| r * i}
end

def key(list)
  list.map{|a,b| [a,b%2]}*","
end

def num(list)
  key = key(list)
  return @memo[key] if @memo[key]
  return list[0][1] % 2 if list.size == 1
  (list.size-1).downto(1) {|i|
    list[i][1]+=1 if list[i][0] % list[0][0] == 0
  }
  val = list[0][1] % 2
  list.delete_at(0)
  @memo[key]||=val+num(list)
  return @memo[key]
end

coins=[]
N=gets.to_i
N.times{ coins << gets.to_i }

total=0.0
coins.permutation() {|perm|
  list=[]
  perm.each {|item| list << [item, 1] }
  ans = num(list)
  total += ans
  #puts "#{perm} count:#{ans}"
}
puts (total/kai(N))

Submission Info

Compile Error

./Main.rb:36: warning: (...) interpreted as grouped expression

Judge Result