How can I generate all possible combinations from multiple lists of varying lengths?

Determining All Combination Sets from Multiple Lists

Seeking a solution to generate a comprehensive list encompassing all possible combinations from a set of undefined lists, each varying in length? Let's explore a more thorough breakdown of this puzzle.

Recursive Approach Unveiled

The key to unraveling this puzzle lies in the elegance of recursion. By cleverly decomposing the problem into smaller, manageable chunks, we can gradually stitch together the tapestry of all possible combinations:

1. Establish a Foundation:

Define an encompassing list of lists, 'lists,' which encapsulates all the lists from which combinations are sought. Additionally, create a target list, 'result,' which will ultimately store the elusive set of unique combinations.

2. Commence the Recursive Descent:

Introducing the 'generatePermutations' method: a recursive function that meticulously explores the labyrinth of possibilities. With each recursive call, it descends deeper into the 'lists' structure, unraveling its contents layer by layer.

3. Depths of Recursion:

The 'depth' parameter demarcates the current depth within the 'lists' structure. As it increments, the function ventures down the list hierarchy, uncovering the nested lists one level at a time.

4. An Empty Canvas:

At the root of the recursive descent, when 'depth' equals the size of 'lists,' a pivotal point emerges. The function recognizes this as the moment to paint its brushstroke on the result canvas. The meticulously crafted 'current' string, which has diligently accumulated characters along the recursive journey, now finds its destined abode in the 'result' list.

5. Unraveling the Layers:

Within the recursive loop, the function systematically iterates through each element of the current list (lists.get(depth)) and seamlessly integrates them into the 'current' string. With each element appended, the recursive descent continues, venturing deeper into the 'lists' structure.

6. The Final Canvas:

Upon completing the recursive dance, the 'result' list proudly displays the sought-after collection of unique combinations, encompassing all permutations borne from the input lists.

A Flawless Composition:

The 'generatePermutations' function, a masterpiece of recursive artistry, gracefully navigates the depths of the 'lists' structure, harmoniously weaving together its elements. With each recursive step, it painstakingly constructs the final tapestry of combinations, leaving no stone unturned in its quest for completeness.

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