#!/usr/bin/perl

use strict;
use warnings;


build_sth( 'set_to_flag' );

sub write_flag{
    print "Success for flag.\n";
}

sub write_sets{print "Success for Set.\n"; }

sub do_nothing{print "Exit Here\n";}

sub build_sth{
    my ($op_code) = @_;
    
    my %Op = (
        set_to_flag => \&write_flag,
        set_tree => \&write_sets,
        default => \&do_nothing
    );
    
    my $op_exec = $Op{$op_code} ;
    if( defined $op_exec ){
        $op_exec->();
    }else{
        print "Oops\n";
    }

}
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