Question

我有这段代码：

super_heroes = [
    ["Spider Man", "Peter Parker"],
    ["Deadpool", "Wade Wilson"],
    ["Wolverine", "James Howlett"]
]

super_heroes.each do |sh|
    sh.each do |heroname, realname|
        puts "#{realname} is #{heroname}"
    end
end

输出是这样的：

 is Spider Man
 is Peter Parker
 is Deadpool
 is Wade Wilson
 is Wolverine
 is James Howlett

但我想成为这样：

Peter Parker is Spider Man
Deadpool is Wade Wilson
Wolverine is James Howlett

经过几个小时的代码迭代，我仍然无法弄明白。如果有人能让我朝着正确的方向前进并解释我做错了什么，我将不胜感激。谢谢！

Answer 1

执行以下操作：

super_heroes = [
    ["Spider Man", "Peter Parker"],
    ["Deadpool", "Wade Wilson"],
    ["Wolverine", "James Howlett"]
]

super_heroes.each do |heroname, realname|
   puts "#{realname} is #{heroname}"
end

# >> Peter Parker is Spider Man
# >> Wade Wilson is Deadpool
# >> James Howlett is Wolverine

你的代码怎么了？

super_heroes.each do |sh| # sh is ["Spider Man", "Peter Parker"] etc..
    # here **heroname** is "Spider Man", "Peter Parker" etc.
    # every ietration with sh.each { .. } your another variable **realname**
    # is **nil**
    sh.each do |heroname, realname| 
        puts "#{realname} is #{heroname}"
        # as **realname** is always **nil**, you got the output as
        # is Spider Man
        # is Peter Parker
        # .....
        # .....
    end
end

Answer 2

也试试这个，

super_heroes.each do |sh|
    puts sh.join(" is ")
end

如何在Ruby中正确访问和迭代多维数组？

2 个答案: