小闭包（参数传参）

<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title></title>
</head>
<body>
<script>
    (function(a,b){
        var num = 10;
        console.log(a+b+num);
    }(1,2));
     (function(a,b){
         var num = 20;
        console.log(a+b+num);
    }(4,5));
</script>
</body>
</html>