Calculate digonal difference in php array matirx
$arr = array( array(11, 2, 4), array(4, 5, 6), array(10, 8, -12), ); echo diagonalDifference($arr); function diagonalDifference($arr) { $n= count($arr); $firstdsum= 0; $seconddsum = 0; $i = 0; for($j = 0; $j < $n; $j++){ $firstdsum+= $arr[$i++][$j]; $seconddsum += $arr[$n- $i][$j]; } return abs($firstdsum- $seconddsum ); }