WordPress tiny plugin - Switch theme on certain pages

1fix-switch-theme-on-certain-pages.php

<?php
/**
 * @package One_Fix_Switch_Theme
 * @version 1.0
 */
/*
Plugin Name: One Fix Switch Theme
Plugin URI: https://www.1fix.io
Description: Switch theme on certain pages.
Author: Yoren Chang
Version: 1.0
Author URI: https://www.1fix.io
*/

function one_fix_switch_theme() {
	add_filter( 'stylesheet', 'one_fix_stylesheet' );
	add_filter( 'template', 'one_fix_template' );
}
add_action( 'setup_theme', 'one_fix_switch_theme' );

function one_fix_stylesheet( $current_theme ) {
	$uri = explode( '/', $_SERVER['REQUEST_URI'] );
	if ( in_array( $uri[1], array( 'slug-a', 'slug-b', 'slug-c' ) ) ) {
		return 'twentythirteen-child';
	} else {
		return $current_theme;
	}
}

function one_fix_template( $current_theme ) {
	$uri = explode( '/', $_SERVER['REQUEST_URI'] );
	if ( in_array( $uri[1], array( 'slug-a', 'slug-b', 'slug-c' ) ) ) {
		return 'twentythirteen';
	} else {
		return $current_theme;
	}
}