perl 递归两例
Perl 作为一门文本处理语言，自然会有他的递归写法，小弟这边分享两个例子，希望对大家能有用！
阶乘(最经典的递归）
#!/usr/bin/perl -s
my $Result = 1;
sub GetResult{
my $num = shift;
if( $num != 1 ){
$Result = $Result * $num;
print "Result:$Result | num:$num\n";
$num--;
GetResult($num);
}
}
GetResult('10');
运行结果：
[root@virfed64 ~]# ./GetResult.pl Result:10 | num:10 Result:90 | num:9 Result:720 | num:8 Result:5040 | num:7 Result:30240 | num:6 Result:151200 | num:5 Result:604800 | num:4 Result:1814400 | num:3 Result:3628800 | num:2
遍历linux的文件目录找出自己想要的文件
[root@virfed64 ~]# cat Scan.pl
#!/usr/bin/perl -s
#
use Cwd;
sub ScanDirectory{
my $workdir = shift;
my $startdir = cwd;
chdir $workdir or die "Unable to enter dir $workdir:$! \n";
opendir my $DIR,'.' or die "Unable to open $workdir:$! \n";
my @names = readdir $DIR or die "Unable to read $workdir:$!\n";
closedir $DIR;
foreach my $name (@names){
next if ($name eq '.');
next if ($name eq '..');
if ( -d $name ){
ScanDirectory($name);
next;
}
if($name eq 'core'){
if (defined $r ){
unlink $name or die "Unable to delete $name :$! \n";
}
else{
print "Found one in $workdir!\n";
}
}
}
chdir $startdir or die "Unable to change to dir $startdir:$!\n";
}
ScanDirectory('.');
运行结果就是找到文件或者删除
转载于:https://blog.51cto.com/realsilsa/1774587