html运行实例（eg_js_mistakes_add

代码示例：（标识：eg_js_mistakes_add_2）

<!DOCTYPE html>
<html>
<body>

<p id="demo"></p>

<script>
var x = 10;
var y = "5";
var z = x + y;
document.getElementById("demo").innerHTML = z;
</script>

</body>
</html>