删除perl中包含重复正则表达式的行

Question

我有一个包含以下元素的数组：

@array = qw/ john jim rocky hosanna/;

INPUT FILE:

john wears blue shirt 

hosanna knows drawing

george and jim went to europe

john went to swimming

jim wears yellow shirt

rocky went to swimming

rocky learns painting

hosanna learns painting

REQUIRED OUTPUT:

john wears blue shirt 

hosanna knows drawing

george and jim went to europe

rocky went to swimming

所以，我只需要第一次出现的行。

Answer 1

@seen{@array} = ();
@out = grep { (($w)=split; !($seen{$w}++) } @in;

Answer 2

perl -ane 'print unless $a{$F[0]}++ ' inputfile

希望这有效+

Answer 3

制作另一个数组来指示该名称是否已被使用怎么样？然后，当您第一次阅读 Jim 的行时，请将此数组中的变量设置为所使用的并写入输出中。如果过去已经使用过，则无需执行任何操作。

@array =(john,jim,rocky,hosanna);
@used =(0,0,0,0);

Answer 4

单程。我将数组数据保存到哈希中，并在输入文件中找到条目时删除该条目。

script.pl 的内容：

use warnings;
use strict;

## Input names to search.
my @array = qw/ john jim rocky hosanna/;

## Save names to a hash. This way they are easier to find out.
my %names = map { $_ => 1 } @array;

## Read file line by line.
while ( <> ) { 

    ## Avoid blank lines.
    next if m/\A\s*\Z/;

    ## Split line in fields.
    my @f = split;

    ## Count number of names in hash.
    my $num_entries = scalar keys %names;

    ## Remove words of hash found in line.
    for ( @f ) { 
        delete $names{ $_ };
    }   

    ## If now there are less names, it means that line had any of
    ## them, so print line.
    if ( scalar keys %names < $num_entries ) { 
        printf qq[%s\n], $_; 
    }   

    ## If hash is empty, there are no lines left to print, so exit of
    ## loop without checking more lines.
    last if scalar keys %names == 0;
}

命令：

perl script.pl infile

输出：

john wears blue shirt 

hosanna knows drawing

george and jim went to europe

rocky went to swimming