Perl-Chapter 6-hash-Exercises

1. Question

2. Code and Output

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". $ 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. File

/Files/pangxiaodong/learns ningperl/ch6-answer.rar