Perl语言入门-第三章-列表与数组-习题

1. 题目

   

2. 代码   

 
   1  
  # 
  -----------------------------------------------------------#
 
   2  
  # Source: Learning Perl, chapter3
 
   3  
  # Date:   2012-01-13
 
   4  
  # Author: xiaodongrush
 
   5  
  #-----------------------------------------------------------#
 
   6  
  #                          code-1                           #
 
   7  
  #-----------------------------------------------------------# 
  
 
   8  
   
  $split =  
  " 
  ------------------------------------------------- 
  "; 
  
 9  
  $code1 =  
  ' 
  chomp(@strs = <STDIN>); 
  '     .  
  " 
  \n 
  " .  
  
10           
  ' 
  foreach(reverse(@strs)) { 
  '   .  
  " 
  \n 
  " . 
  
11           
  ' 
    print $_ . "\n"; 
  '               .  
  " 
  \n 
  " . 
  
12           
  ' 
  } 
  '; 
  
13  
  print  
  " 
  code-1\n 
  " .  
  $code1 .  
  " 
  \n 
  " .  
  $split; 
  
14  
  # 
  -----------------------------------------------------------#
 
  15  
  #                          execute-1                        #
 
  16  
  #-----------------------------------------------------------# 
  
 
  17  
   
  print  
  " 
  \nexecute-1\n 
  "; 
  
18  
  chomp( 
  @strs = <STDIN>); 
  
19  
  foreach( 
  reverse( 
  @strs)) { 
  
20    
  print  
  $_ .  
  " 
  \n 
  "; 
  
21 } 
  
22  
  # 
  -----------------------------------------------------------#
 
  23  
  #                          code-2                           #
 
  24  
  #-----------------------------------------------------------# 
  
 
  25  
   
  $code2 =  
  ' 
  @names = qw { fred betty barney dino wilma pebbles bamm-bamm }; 
  '     .  
  " 
  \n 
  " .  
  
26           
  ' 
  chomp(@indexes=<STDIN>); 
  '                                            .  
  " 
  \n 
  " . 
  
27           
  ' 
  foreach(@indexes) { 
  '                                                 .  
  " 
  \n 
  " . 
  
28           
  ' 
    print @names[($_-1)%7] . "\n"; 
  '                                    .  
  " 
  \n 
  " . 
  
29           
  ' 
  } 
  '; 
  
30  
  print  
  $split .  
  " 
  \ncode-2\n 
  " .  
  $code2 .  
  " 
  \n 
  " .  
  $split; 
  
31  
  # 
  -----------------------------------------------------------#
 
  32  
  #                          execute-2                        #
 
  33  
  #-----------------------------------------------------------# 
  
 
  34  
   
  print  
  " 
  \nexecute-2\n 
  "; 
  
35  
  @names = qw { fred betty barney dino wilma pebbles bamm-bamm }; 
  
36  
  chomp( 
  @indexes=<STDIN>); 
  
37  
  foreach( 
  @indexes) { 
  
38    
  print  
  @names[( 
  $_- 
  1)% 
  7] .  
  " 
  \n 
  "; 
  
39 } 
  
40  
  # 
  -----------------------------------------------------------#
 
  41  
  #                          code-3                           #
 
  42  
  #-----------------------------------------------------------# 
  
 
  43  
   
  $code3 =  
  ' 
  chomp(@strs=<STDIN>); 
  '      .  
  " 
  \n 
  " .  
  
44           
  ' 
  foreach(sort(@strs)) { 
  '     .  
  " 
  \n 
  " . 
  
45           
  ' 
    print $_ . " "; 
  '          .  
  " 
  \n 
  " . 
  
46           
  ' 
  } 
  '                          .  
  " 
  \n 
  " . 
  
47           
  ' 
  print "\n"; 
  '                .  
  " 
  \n 
  " . 
  
48           
  ' 
  foreach(sort(@strs)) { 
  '     .  
  " 
  \n 
  " . 
  
49           
  ' 
    print $_ . "\n"; 
  '         .  
  " 
  \n 
  " . 
  
50           
  ' 
  } 
  '; 
  
51  
  print  
  $split .  
  " 
  \ncode-3\n 
  " .  
  $code3 .  
  " 
  \n 
  " .  
  $split; 
  
52  
  # 
  -----------------------------------------------------------#
 
  53  
  #                          execute-3                        #
 
  54  
  #-----------------------------------------------------------# 
  
 
  55  
   
  print  
  " 
  \nexecute-3\n 
  "; 
  
56  
  chomp( 
  @strs=<STDIN>); 
  
57  
  foreach( 
  sort( 
  @strs)) { 
  
58    
  print  
  $_ .  
  " 
    
  "; 
  
59 } 
  
60  
  print  
  " 
  \n 
  "; 
  
61  
  foreach( 
  sort( 
  @strs)) { 
  
62    
  print  
  $_ .  
  " 
  \n 
  "; 
  
63 } 
  
64  
  # 
  -----------------------------------------------------------# 
  
 
  65  
   
  print  
  " 
  END!!! 
  "; 
  
66 <STDIN> 
  
67  
  # 
  -----------------------------------------------------------#
 
  68  
  # 总结
 
  69  
  # 1. @str_array = <STDIN>; 每次读入一行，数组增加一个元素，
 
  70  
  #    直到读入文件为空或者输入Control+Z(Windows),Control+D(Unix)
 
  71  
  # 2. $_表示一些省略参数的变量，比如foreach()省略，print的省略。
 
  72  
  # 3. reverse，sort，这些函数与chomp不同，更像返回值，而chomp直接修改了原数组，或者原变量 
 

3. 输出

   

   

   

4. 文件

    /Files/pangxiaodong/LearningPerl/ch3-answer.rar