Ruby的字符串与数组求最大值的相关问题讨论_ruby专题_

 b=[1,3,55,777,2,4,6,8,0] 

 b.max => 777 b.min => 0 

 # enum.max -> obj # enum.max { |a, b| block } -> obj #a = %w(albatross dog horse) #a.max => "horse" # a.max { |a, b| a.length <=> b.length } #=> "albatross" 

 d=%w(albatross dog horse ddd dasgfds) d.max => "horse" 

 a = ["1", "3", "55", "777", "2", "4", "6", "8", "0"] def max(first,*rest) max=first rest.each do |x| p "---#{x}---#{max}" max=x if x>max p "---#{x}---#{max}" max end 

 "---3---1" "---3---3" "---55---3" "---55---55" "---777---55" "---777---777" "---2---777" "---2---777" "---4---777" "---4---777" "---6---777" "---6---777" "---8---777" "---8---8" "---0---8" "---0---8" => "8" 

 "7" > "777" => false "6" > "777" => false "9" > "777" => true "10" > "777" => false "11" > "777" => false "70" > "777" => false "80" > "777" => true 

 ary.sort -> new_ary ary.sort { |a, b| block } -> new_ary enum.sort_by { |obj| block } -> array enum.sort_by -> an_enumerator 

 h=['1','3','13','10','7'] A. p h.sort B. p h.sort{|a,b| a.to_i <=> b.to_i} C. p h.sort_by{|x| x.to_i} 

 A. ["1", "10", "13", "3", "7"] B. ["1", "3", "7", "10", "13"] C. ["1", "3", "7", "10", "13"]