regex - Perl 中的匹配计数

Question

我有一个带有各种关键字的哈希。现在，我想在字符串中找到这些关键字的计数。

我刚刚用 foreach 循环编写了部分代码。

use strict;
use warnings;

my $string = "The invitro experiments are conducted on human liver microsom. "
          . " These liver microsom can be cultured in rats.";

my %hash = (
    "human"     => 1,
    "liver"     => 1,
    "microsom"  => 1,
);

for my $nme (keys %hash){
        # Some code which I am not sure
}

预期输出：human:1; liver:2; microsom:3

有人可以帮助我吗？

谢谢

Answer 1

以下代码段应该足够了。

#!/usr/bin/perl -w

use strict;

my $string="The invitro experiments are conducted on human liver microsom. These liver   microsom can be cultured in rats.";

my %hash = (
'human' => 1,
'liver' => 1,
'microsom' => 1,
);

my @words = split /\b/, $string;

my %seen;

for (@words) {
    if ($_ eq 'human' or $_ eq 'liver' or $_ eq 'microsom') {
        $seen{$_}++;
    }
}

for (keys %hash) {
    print "$_: $seen{$_}\n";
}

Answer 2

可能不是解决此问题的最佳方法，但它应该可以工作。

my $string = "The invitro experiments are conducted on human liver microsom. These liver microsom can be cultured in rats.";

my %hash = (
    'human' => 1,
    'liver' => 1,
    'microsom' => 1,
);

foreach my $nme (keys %hash){
    $hash{$nme} = scalar @{[$string =~ /$nme/g]};
    print "$hash{$nme}\n";
}

Answer 3

那是家庭作业吗？:) 好吧，取决于散列中的单词数和字符串（字符串）中的单词数，它会更好地迭代散列，或者迭代字符串中的单词，找到时增加适当的值。由于您需要检查所有单词，因此您将以一个列表结尾，其中一些标记为“0”，一些标记为大于零。