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    2. <html lang="en">
    3. <head>
    4.     <meta charset="UTF-8">
    5.     <meta name="viewport" content="width=device-width, initial-scale=1.0">
    6.     <title>Document</title>
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    8. <body>
    9.     <script>
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    12.         var b = [4,5,6];
    13.         // [1,2,3,4,5,6]
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    17. </body>
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