Check duplicate values in PHP array

method1.php

<?php
/*Check duplicate values in PHP array*/
$country_array = [];
$args = array(
    'post_type' => 'distributor',
    'posts_per_page' => '-1'
);
$loop = new WP_Query($args);
while($loop->have_posts()): $loop->the_post();
    $id = get_the_ID();
    $title = get_the_title();
    $country_filter = get_field('country_filter');

    if (!empty($country_filter)) {
        foreach ($country_filter as $key => $value_filter) {
            array_push($country_array, $value_filter);
        }           
    }

endwhile;
wp_reset_query();
$country_array = array_unique($country_array);

foreach ($country_array as $key => $label) {
    $value = sanitize_title($label);
    echo '<pre>';
    var_dump($label);
    echo '</pre>';
}

method2.php

<?php
/*Check duplicate values and count in PHP array*/
$country_array = [];
$args = array(
    'post_type' => 'distributor',
    'posts_per_page' => '-1'
);
$loop = new WP_Query($args);
while($loop->have_posts()): $loop->the_post();
    $id = get_the_ID();
    $title = get_the_title();
    $country_filter = get_field('country_filter');

    if (!empty($country_filter)) {
        foreach ($country_filter as $key => $value_filter) {
            array_push($country_array, $value_filter);
        }           
    }

endwhile;
wp_reset_query();
$array_count_values = array_count_values($country_array);

foreach ($array_count_values as $label => $key) {
    $value = sanitize_title($label);
    echo '<pre>';
    var_dump($label);
    echo '</pre>';
}