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# 7.2 練習：陣列項目不能重覆

## 練習：陣列項目不能重覆

提供一個陣列：

```javascript
let line_ids = ["a", "b", "c", "a", "y", "c"];
```

撰寫 jQuery 語法，執行迴圈，將重覆的 line\_id 移除。

印出結果如下：

```javascript
["a","b","c","y"]
```

參考作法：

{% embed url="<https://codepen.io/carlos411/pen/QWKeXBX>" %}