Perl语言入门-第五章-输入与输出-习题

haoman

　　1. 习题

　　2. 代码与输出
　　cat_reverse.pl


1 #-----------------------------------------------------------#
2 # Source: Learning Perl, chapter5, exercise-1
3 # Date:   2012-01-15
4 # Author: xiaodongrush
5 #-----------------------------------------------------------#
6 use 5.010;
7 while(<>) { chomp; unshift @array,$_; }
8 foreach(@array) { say $_; }
9 <STDIN>
10 # @_表示子程序的参数列表，$_是Perl的老地方，容易混淆
　　printf_example.pl


1 #-----------------------------------------------------------#
2 # Source: Learning Perl, chapter5, exercise-2
3 # Date:   2012-01-15
4 # Author: xiaodongrush
5 #-----------------------------------------------------------#
6 use 5.010;
7 say "Input several str! (Use Control+Z to Stop Input).";
8 while(<>) { chomp; push @strs,$_; }
9 say "1234567890" x 4;
10 foreach(@strs) { printf "%20s\n",$_; }
11 <STDIN>
　　printf_example_2.pl


1 #-----------------------------------------------------------#
2 # Source: Learning Perl, chapter5, exercise-3
3 # Date:   2012-01-15
4 # Author: xiaodongrush
5 #-----------------------------------------------------------#
6 use 5.010;
7 say "Input several str! (Use Control+Z to Stop Input).";
8 while(<>) { chomp; push @strs,$_; }
9 print "The Width of the Rule Line Width = "; $width = <STDIN>;
10 print "1234567890" x ($width/10);
11 foreach(1..9) { if($_ <= ($width%10)) { print $_; } } say;
12 foreach(@strs) { printf "%20s\n",$_; }
13 <STDIN>
　　3. 文件
　　/Files/pangxiaodong/LearningPerl/ch5-answer.rar