Perl语言入门-第六章-哈希-习题

最新推荐文章于 2025-06-20 13:29:46 发布

转载最新推荐文章于 2025-06-20 13:29:46 发布 · 116 阅读

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CC 4.0 BY-SA版权

原文链接：http://www.cnblogs.com/pangxiaodong/archive/2012/01/16/2323406.html

本文提供了三个使用Perl语言处理哈希的示例程序，包括查找家庭成员姓氏、统计单词出现次数及展示环境变量哈希。这些代码展示了如何利用Perl哈希解决实际问题。

1. 题目

2. 代码与输出

ch6-family-name.pl

1 # -----------------------------------------------------------#
2 # Source: Learning Perl, chapter6, exercise-1
3 # Date:   2012-01-16
4 # Author: xiaodongrush
5 #-----------------------------------------------------------#
6 use 5.010;
7 %family_name_hash = (
8    " fred "   =>   " flintstone ",
9    " barney " =>   " rubble ",
10    " wilma "  =>   " flintstone ", );
11
12 while(<>) {
13    chomp;
14    if( exists $family_name_hash{ $_} ) {
15     say $_ . " 's family name is : " . $family_name_hash{ $_};
16   } else {
17     say $_ . " 's family name not exist in hash ";
18   }
19 }
20 # -----------------------------------------------------------#

ch6-wordcount.pl

1 # -----------------------------------------------------------#
2 # Source: Learning Perl, chapter6, exercise-2
3 # Date:   2012-01-16
4 # Author: xiaodongrush
5 #-----------------------------------------------------------#
6 use 5.010;
7 while(<>) {
8    chomp;
9    if( exists $word_hash{ $_}) {
10      $word_hash{ $_} += 1;
11   } else {
12      $word_hash{ $_} = 1;
13   }
14 }
15 foreach( sort ( keys %word_hash) ) {
16   say $_ . " \t\t " . $word_hash{ $_};
17 }
18 # -----------------------------------------------------------#

ch6-ENV-hash.pl

1 # -----------------------------------------------------------#
2 # Source: Learning Perl, chapter6, exercise-3
3 # Date:   2012-01-16
4 # Author: xiaodongrush
5 #-----------------------------------------------------------#
6 use 5.010;
7
8 $max_key_len = 0;
9 $max_value_len = 0;
10 $len_limit = 35;
11 while(( $key, $value) = each %ENV) {
12    if( length( $key) < $len_limit  && length( $value) < $len_limit ) {
13      $max_key_len = $max_key_len > length( $key) ? $max_key_len : length( $key);
14      $max_value_len = $max_value_len > length( $value) ? $max_value_len : length( $value);
15   }
16 }
17 $format = " %- " . $max_key_len . " s  ,  %- " . $max_value_len . " s\n ";
18 printf $format, " key ", " value ";
19 foreach( sort( keys %ENV)) {
20    if( ( length( $_) < $len_limit ) && ( length( $ENV{ $_}) < $len_limit )) {
21      printf $format, $_, $ENV{ $_};
22   }
23 }
24 <STDIN>;
25 # -----------------------------------------------------------#

3. 文件

/Files/pangxiaodong/LearningPerl/ch6-answer.rar

转载于:https://www.cnblogs.com/pangxiaodong/archive/2012/01/16/2323406.html