\n\n"; if(isset($_POST["operation"]) && isset($_POST["t1"]) && isset($_POST["t2"]) ) { $op = $_POST['operation']; $t1 = $_POST['t1']; $t2 = $_POST['t2']; if($op === "plus") echo ($t1 + $t2); else if($op === "minus") echo ($t1 - $t2); else if($op === "times") echo ($t1 * $t2); else if($op === "divide" && abs($t2) > 1e-10) echo ($t1 / $t2); else echo 'expr_post.php? operation=(plus|minus|times|divide)?t1=(float)?t2=(float)'; } else { echo 'expr_post.php?operation= (plus|minus|times|divide)?t1=(float)?t2=(float) '; print_r($_POST); } echo "\n"; ?>