使用带有模板部分的index.php从wordpress中排除重复的帖子

I'm trying to avoid duplicates posts in one file - index.php where i do collection of the loops for categories. But no result. Please - help...

<div class="container-fluid newgray">
    <div class="container asia travel-news proppad">
        <?php get_template_part( 'inc/slider-news' );?>     
    </div>
</div>
<div class="container-fluid best">
    <div class="container travel-news proppad">
        <?php get_template_part( 'inc/best' );?>
    </div>
</div>
<div class="container-fluid newback over">
    <div class="container last travel-news proppad">
        <?php get_template_part( 'inc/latest' );?>      
    </div>
</div>

Trying use this code:

<?php
$do_not_duplicate = array(); // set befor loop variable as array

// 1. Loop
query_posts('ca=1,2,3&showposts=5');
while ( have_posts() ) : the_post();
    $do_not_duplicate[] = $post->ID; // remember ID's in loop
    // display post ...
    the_title();
endwhile;
?>

<?php
// 2. Loop
query_posts( 'cat=4,5,6&showposts=15' );
while (have_posts()) : the_post();
    if ( !in_array( $post->ID, $do_not_duplicate ) ) { // check IDs         
// display posts ...
        the_title();
    }
endwhile;
?>

But it works only when all loops in one php file…

This is How I wold do, don't waste your time repeating same code, it will be a hell if you need change something.

function post_by_cat_ecluding($cats, $per_page, $exclude =  array()) {
    $html = '';
    $args = array(
        'post_type' => 'post',
        'post_status' => 'publish',
        'category__in' => $cats,
        'posts_per_page' => $per_page,
        'post__not_in' => $exclude,
        'offset' => 0
    );
    $loop = new WP_Query($args);

    foreach ($loop->posts as $p) {
        $exclude[] = $p->ID;
        $html .= '<article><h2>'.$p->post_title.'</h2></article>';
    }

    return array('html' => $html, 'exclude' => $exclude);
}

$first_block = post_by_cat_ecluding(array(1,2), 5);
echo $first_block['html'];

$second_block = post_by_cat_ecluding(array(4,5), 15, $first_block['exclude']);
echo $second_block['html'];