求助：perl格式化数组

815138698

Write a function, format_number_list, whose argument is a list of integers.  It then returns a string which represents the input list in compact, human-readable form.
For example,
         format_number_list (1, 2, 4, 5, 6, 7, 9, 13, 24, 25, 26, 27)
will return
        "1-2, 4-7, 9, 13, 24-27"
Also write a function, 'expand_number_list', which does the conversion in the opposite direction, so that
        expand_number_list("1-2, 4-7, 9, 13, 24-27")
will return
        (1, 2, 4, 5, 6, 7, 9, 13, 24, 25, 26, 27)

MMMIX

题目不错呀

rubyish

biru:

1. #!/usr/bin/perl
   
2. use 5.022;
   
3. 
   
4. sub Join {
   
5.     my @a = [shift];
   
6.     $_ - $a[-1][-1] > 1 ? push @a, [$_] : ( $a[-1][1] = $_ ) for @_;
   
7.     join ', ', map { join '-', @$_ } @a;
   
8. }
   
9. 
   
10. sub Split {
    
11.     map { @_ = /\d+/g; $_[0] .. $_[$#_] } split ', ', pop;
    
12. }
    
13. 
    
14. my @input = ( 1, 2, 4, 5, 6, 7, 9, 13, 24, 25, 26, 27 );
    
15. my $list  = Join @input;
    
16. my @list  = Split $list;
    
17. 
    
18. say "@input";
    
19. say $list;
    
20. say "@list";
    

复制代码

MMMIX

回复 3# rubyish


    Join 的实现可以再稍微简化下，就和上面的 Split 风格更一致了：

1. 
   
2. map { @_ = split '-'; $_[0] .. $_[-1] } split ', ', pop;
   

复制代码

rubyish

回复 4# MMMIX

    map { @_ = split '-'; $_[0] .. $_[-1] } split ', ', pop;

3Q ~ xiangbudao  -1
split '-' : 9 chars
/\d+/g : 6 chars

MMMIX

回复 5# rubyish


    你在 Split 里面 -1 用的挺好的呀。

/\d+/g 更短这个还真没注意，我主要是考虑到在 Split 里面用了两个 join, 刚好能和 Join 里面的两个 split 对上，然后看起来会更对称一些。