Exclude Category from Post’s Category List

For some reason, maybe you want to exclude one or two categories for the list. This can be achieved by hacking the_category function, or create a new code to list the category, to replace the_category.
<?php
foreach ((get_the_category())  as $category) {
if ( $category ->cat_name != 'cat_to_exclude') {
echo'<a href="'. get_category_link( $category->term_id ) .
'" title="'. sprintf( __( "View all posts in %s" ), $category->name ) . '"' . '>'. $category->name.'</a> ';
}
}
?>

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