perl 数组对比 删相同元素

Question

perl 数组对比 删相同元素

Answer 1

这是经典的集合差运算，下面的代码还演示了集合并集、交集的运算，只是没有输出结果，请自行理解，完整代码如下：@a=('1','2','3','4');@b=('1','3');@union=();#并集@diff=(); #差集@isect=();#交集foreach $e(@a,@b){$union{$e}++&&$isect{$e}++;}@union=keys %union;@isect=keys %isect;@diff=grep {$union{$_}==1;} @union;print join(',', @a),"\n";print join(',', @b),"\n";print join(',', @diff),"\n";

Answer 2

my %h = ();++$h{$_} foreach ( @array1, @array2 );my @array3 = sort keys %h;

Answer 3

my @array1 = ('aa', 'bb');my @array2 = ('cc', 'aa');@array3 = (@array1, @array2);my %count;my @array3_new = grep { ++$count{ $_ } < 2; } @array3;print @array3_new;或者@array3 = (@array1, @array2);foreach my $item ( @array3 ){if ( ! grep( /$item/, @array3_new ) ){push( @array3_new, $item );}}print @array3_new;