Ruby如果數組的元素是這些字符之一，則比較

Question

g = [["xx", "A"],­ ["xx", "B"]]­ 
g.any?{­|x,y| y.eq­l? ("A"|­|"B"||"C"­)} 

我想評估子數組中的第二個元素是「A」還是「B」或「C」之一。在上述情況下，應返回true。並返回false，例如，if g=[["xx","K"]["xx","B"]。

Answer 1

我想出上述兩種答案

1.9.3p194 :177 > g =[["xx", "A"],["xx", "B"]] 
=> [["xx", "A"], ["xx", "B"]] 
1.9.3p194 :178 > g.all? {|i,v| "ABC".include?v} 
=> true #correctly return true 
1.9.3p194 :179 > g =[["xx", "A"],["xx", "Ba"]] 
=> [["xx", "A"], ["xx", "Ba"]] 
1.9.3p194 :180 > g.all? {|i,v| "ABC".include?v} 
=> false #correctly return false 

編輯的組合後，通過@勝利者的回答啓發基準

array= ['A','B','C'] 
g.all? { |x,y| arr.include?y 

和

h = {"A" => true, "B" => true, "C" => true} 
g.all? { |x,y| h.has_key?(y) 

都是贏家。

基準的通過@victor答案

require 'benchmark' 

many = 500000 

g = [["x", "A"], ["xx", "B"]] 
h = {"A" => true, "B" => true, "C" => true} 
arr = ['A','B','C'] 

Benchmark.bm do |b| 
    b.report("regexp1\t") {many.times { g.all? { |x,y| y =~ /^(A|B|C)$/} } } 
    b.report("regexp2\t") { many.times { g.all? { |x,y| y =~ /^[ABC]$/ } } } 
    b.report("hash\t") { many.times { g.all? { |x,y| h.has_key?(y) } } } 
    b.report("str include\t") { many.times { g.all? { |x,y| "ABC".include?y } } } 
    b.report("array include\t") { many.times { g.all? { |x,y| arr.include?y } } } 
end 

#Output 
     user  system  total  real 
regexp1   0.640000 0.000000 0.640000 ( 0.635750) 
regexp2   0.580000 0.000000 0.580000 ( 0.586788) 
hash    0.370000 0.000000 0.370000 ( 0.364140) 
str include  0.430000 0.010000 0.440000 ( 0.439753) 
array include  0.380000 0.010000 0.390000 ( 0.381149) 

乾杯啓發。

Answer 2

如何：

g.all? { |x,y| y =~ /^(A|B|C)$/ } 

編輯：後@ PriteshJ的觀察

Answer 3

我覺得("A" || "B" || "C")送花兒給人給你"A"。

g.each{|x, y| puts "ABC".include? y} 

Answer 4

看起來好老哈希比正則表達式快：

require 'benchmark' 

many = 500000 

g = [["x", "A"], ["xx", "B"]] 
h = {"A" => true, "B" => true, "C" => true} 
Benchmark.bm do |b| 
    b.report("regexp") { many.times { g.all? { |x,y| y =~ /^(A|B|C)$/ } } } 
    b.report("hash") { many.times { g.all? { |x,y| h.has_key?(y) } } } 
end 

# regexp 1.690000 0.000000 1.690000 ( 1.694377) 
# hash 1.040000 0.000000 1.040000 ( 1.040016)