Ruby Tree Printing Method

You are an expert software engineer that understands all aspects of the Ruby programming language (version 3).

Consider the following tree structure:

. ├── 1 │ ├── 1.1 │ │ ├── 1.1.1 │ │ ├── 1.1.2 │ │ └── 1.1.3 │ ├── 1.2 │ │ ├── 1.2.1 │ │ ├── 1.2.2 │ │ └── 1.2.3 │ └── 1.3 │ ├── 1.3.1 │ ├── 1.3.2 │ └── 1.3.3 ├── 2 │ ├── 2.1 │ │ ├── 2.1.1 │ │ ├── 2.1.2 │ │ └── 2.1.3 │ ├── 2.2 │ │ ├── 2.2.1 │ │ ├── 2.2.2 │ │ └── 2.2.3 │ └── 2.3 │ ├── 2.3.1 │ ├── 2.3.2 │ └── 2.3.3 └── 3 ├── 3.1 │ ├── 3.1.1 │ ├── 3.1.2 │ └── 3.1.3 ├── 3.2 │ ├── 3.2.1 │ ├── 3.2.2 │ └── 3.2.3 └── 3.3 ├── 3.3.1 ├── 3.3.2 └── 3.3.3 Each node within this tree is labed by the parent node plus it's position with the parent.

For example, 3.3.2 is the 2nd child of 3.3, 3.3 is the 3rd child of 3, and 3 is the 3rd child of the root (.)

Write a Ruby method that will take two properties:

max_depth (Integer) indicates how many times nodes should be nested. The node 3.3.3 is at a depth of 2, meaning the are two parent nodes before the root node.

items_per_depth (Integer) is the number of children each node should have.

Have the method simply print the node values. For example, print_tree(max_depth: 2, items_per_depth: 3) should print out the following:

1 1.1 1.1.1 1.1.2 1.1.3 1.2 1.2.1 1.2.2 1.2.3 1.3 1.3.1 1.3.2 1.3.3
2 2.1 2.1.1 2.1.2 2.1.3 2.2 2.2.1 2.2.2 2.2.3 2.3 2.3.1 2.3.2 2.3.3
3 3.1 3.1.1 3.1.2 3.1.3 3.2 3.2.1 3.2.2 3.2.3 3.3 3.3.1 3.3.2 3.3.3

To achieve this task in Ruby, we can use a recursive approach. The method will build and print the tree structure based on the specified max_depth and items_per_depth. Recursion is a natural fit for this problem because a tree structure inherently involves repeating a pattern at each level of the tree.

Here is a Ruby method that accomplishes this:

ruby
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1def print_tree(max_depth: , items_per_depth: , current_depth: 0, prefix: '')
2  if current_depth <= max_depth
3    items_per_depth.times do |i|
4      # Constructing the node label
5      node_label = prefix.empty? ? "#{i + 1}" : "#{prefix}.#{i + 1}"
6
7      # Printing the node label
8      puts node_label
9
10      # Recursively calling print_tree to handle the next level of the tree
11      print_tree(max_depth: max_depth, items_per_depth: items_per_depth, current_depth: current_depth + 1, prefix: node_label)
12    end
13  end
14end
15
16# Example usage
17print_tree(max_depth: 2, items_per_depth: 3)

This method works as follows:

1. It checks if the current depth is less than or equal to max_depth. If it is, it proceeds to generate the nodes for that depth.
2. It uses a loop (running items_per_depth times) to generate each node at the current level.
3. It constructs the label for each node by appending the current index to the prefix passed to the function.
4. It prints the node label.
5. It then recursively calls itself to handle the next level of the tree, increasing the current depth by 1 and passing the new node label as the prefix.

The method will print the tree structure as per the example you provided when called with print_tree(max_depth: 2, items_per_depth: 3).