Hi, before you ask, yes, this is an exercise, and no, it's not for school. In fact what it's for barely matters any more as I've lost the opportunity I'm sure, but given that I don't like to let things lie unsolved, I could use a hand. Basically I've got a nth level deep array of keys to values which are arrays that I need to "flatten". It's easier to explain by looking at the data structure so here you go: 
my $data_struct = [
          'D',
          [
            'C',
            [
              'D',
              [
                'C',
                [
                  'D',
                  'E'
                ],
                'E',
                [
                  'B'
                ]
              ],
              'E',
              [
                'B',
                [
                  'C'
                ]
              ]
            ],
            'E',
            [
              'B',
              [
                'C',
                [
                  'D',
                  'E'
                ]
              ]
            ]
          ],
          'E',
          [
            'B',
            [
              'C',
              [
                'D',
                [
                  'C',
                  'E'
                ],
                'E',
                [
                  'B'
                ]
              ]
            ]
          ],
          'B',
          [
            'C',
            [
              'D',
              [
                'C',
                [
                  'D',
                  'E'
                ],
                'E',
                [
                  'B'
                ]
              ],
              'E',
              [
                'B',
                [
                  'C'
                ]
              ]
            ]
          ]
        ];

[download]
What I need to do is turn it into something like: 
my $flattened = [
[D, C, D, C, D],
[D, C, D, C, E],
[D, C, D, E, B],
[D, C, E, B, C],
etc..
]

[download]
I've banged my head on this for a while, any input/hints would be greatly appreciated.

In reply to A maybe(?) interesting comp-sci type problem by Anonymous Monk

Title:
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