3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr = array( array('city' => 'NewYork', 'cash' => '1000'), array('city' => 'Philadelphia', 'cash' => '2300'), array('city' => 'NewYork', 'cash' => '2000'), ); $newarray = array(); foreach($arr as $ar) { foreach($ar as $k => $v) { if(array_key_exists($v, $newarray)) $newarray[$v]['cash'] = $newarray[$v]['cash'] + $ar['cash']; else if($k == 'city') $newarray[$v] = $ar; } } print_r($newarray);

preferences:
52.28 ms | 402 KiB | 5 Q