public function testQuery()
{
$sentences = ['my blue car', 'red and blue flowers', 'his blue car'];
$chain = new MarkovChain();
foreach ($sentences as $sentence) {
$tokens = explode(" ", $sentence);
$chain->train($tokens);
}
$this->assertEquals(['car' => 0.66666666666667, 'flowers' => 0.33333333333333], $chain->query("blue"));
}
