# [Stax](https://github.com/tomtheisen/stax), <s>12</s> 14 [bytes](https://github.com/tomtheisen/stax/blob/master/docs/packed.md#packed-stax)

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[Run and debug it](https://staxlang.xyz/#p=81f6beb9bf97de4cd432742a85f6&i=[[11,+28],+[12,+16],+[4],+[]],+2%0A[[11,+28],+[12,+16],+[4],+[]],+5%0A[[7,+144],+[12],+[4,+8],+[3,+4,+6]],+1%0A[[7,+144],+[12],+[4,+8],+[3,+4,+6]],+10%0A[[30],+[40],+[50,+60],+[70,+80,+90]],+2%0A[[30],+[40],+[50,+60],+[80,+90]],+7%0A[[15],+[30],+[2,+3,+5],+[4,+5,+10]],+3%0A[[15],+[30],+[2,+3,+5],+[4,+5,+10]],+7&m=2)

Explanation:

    vsc{%1>fr$r+@]|u Full program, unpacked, implicit input
    vs               Decrement the number and get the list
      c{   f         Copy and filter:
        %1>            Length greater than 1?
            r$r      Reverse, flatten, and reverse again
               +     Concat orig array and and modified array
                @]|u Index, wrap into array, uneval