use warnings;
use strict;

use Data::Dumper;

my %app_map;

open my $fh1, '<', 'app.txt' or die $!;

while (my $line = <$fh1>){
    my ($app, $mem, $lang) = split /\s+/, $line;
    $app_map{$app}{mem} = $mem;
    $app_map{$app}{lang} = $lang;
}

close $fh1 or die $!;

open my $fh2, '<', 'app2.txt' or die $!;

while (my $line = <$fh2>){
    my ($app, $cpu, $cores) = split /\s+/, $line;
    $app_map{$app}{cpu} = $cpu;
    $app_map{$app}{cores} = $cores;
}

close $fh2 or die $!;

print Dumper \%app_map;