3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = array("a" =>"b", "c"=>"d"); if(isset($a['a'])) echo "hi"; else echo "hello"; $b = array("a","b","c"); if(in_array('a',$b)) echo "hi"; else echo "hello"; var_dump(array_merge(array("1","2"), array("2","3","4")));

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