映射在一个语句中初始化和递增

Question

如何在一行中增加地图条目，请参阅下面的注释。

$results = array();

# ...  compute $results

# I would like to replace below with one statement, is it possible?
if (!array_key_exists("cnt", $results)) {
   $results["cnt"] = 1; # first time
} else {
   $results["cnt"] += 1;
}

Answer 1

<?php
    $results["cnt"] = !array_key_exists("cnt", $results) ? 1 :  $results["cnt"] + 1;