读 《C程序员精通Perl》http://book.douban.com/subject/1232075/ 2.6节 笔记
while循环:
#!/usr/bin/perl
use strict;
use warnings;
my $number = 1;
my $square;
while (1) {
$square = $number ** 2;
print "$number square is $square\n";
++$number;
if ($number > 10) {
last;
}
}
运行结果:
[root@localhost perl_practice]# ./square_while.pl
1 square is 1
2 square is 4
3 square is 9
4 square is 16
5 square is 25
6 square is 36
7 square is 49
8 square is 64
9 square is 81
10 square is 100
[root@localhost perl_practice]#
for循环
#!/usr/bin/perl
use strict;
use warnings;
my $number;
my $square;
for ($number=0; $number<=10; ++$number) {
if ($number == 8) {
print "number=$number, This is next\n";
next;
}
$square = $number ** 2;
print "$number square is $square\n";
}
运行结果:
[root@localhost perl_practice]# ./square_for.pl
0 square is 0
1 square is 1
2 square is 4
3 square is 9
4 square is 16
5 square is 25
6 square is 36
7 square is 49
This is next
9 square is 81
10 square is 100
[root@localhost perl_practice]#