Binary tree of directories UNIX - bash

Question

I have a task to create a binary tree of directories in bash shell, the depth is given as a first argument of the script. Every directory has to be named with the second argument + the depth of the tree which the directory is in.
Example: ./tree.sh 3 name should create the following structure:
name11
/ \
name21 name22
/ \ / \
name31 name32 name33 name34
I don't really have an idea how to do this, Can't even start. It is harder than anything i have done in bash up until now.. Any help will be very much appreciated.
Thanks in advance.

Answer 1

With recursion:
#!/bin/bash
level=$1
current_level=$2; current_level=${current_level:=1}
last_number=$3; last_number=${last_number:=1}
prefix="name"
# test to stop recursion
[[ $level -eq $(($current_level-1)) ]] && exit
# first node
new_number=$(($current_level*10+$last_number*2-1))
mkdir "$prefix$new_number"
(
cd "$prefix$new_number"
$0 $level $(($current_level+1)) $(($last_number*2-1)) &
)
# second node, not in level 1
if [[ $current_level -ne 1 ]]; then
new_number=$(($current_level*10+$last_number*2))
mkdir "$prefix$new_number"
cd "$prefix$new_number"
$0 $level $(($current_level+1)) $(($last_number*2)) &
fi
Test with ./tree.sh 3

Answer 2

Even though other languages are more suitable in implementing a link list, I don't know why this post got a negative vote.
Here's this expert, shared something good for searching, take a look:
https://gist.github.com/iestynpryce/4153007
NOTE: An implementation of a Binary Sort Tree in Bash. Object-like behaviour has been faked using eval. Remember that eval in shell scripting can be evil. BT and BST have difference, you can google it.
#!/bin/bash
#
# Binary search tree is of the form:
# 10
# / \
# / \
# 4 16
# / \ /
# 1 7 12
#
# Print the binary search tree by doing a recursive call on each node.
# Call the left node, print the value of the current node, call the right node.
# Cost is O(N), where N is the number of elements in the tree, as we have to
# visit each node once.
print_binary_search_tree() {
local node="$*";
# Test is the node id is blank, if so return
if [ "${node}xxx" == "xxx" ]; then
return;
fi
print_binary_search_tree $(eval ${node}.getLeftChild)
echo $(${node}.getValue)
print_binary_search_tree $(eval ${node}.getRightChild)
}
### Utility functions to generate a BST ###
# Define set 'methods'
set_node_left() {
eval "${1}.getLeftChild() { echo "$2"; }"
}
set_node_right() {
eval "${1}.getRightChild() { echo "$2"; }"
}
set_node_value() {
eval "${1}.getValue() { echo "$2"; }"
}
# Generate unique id:
gen_uid() {
# prefix 'id' to the uid generated to guarentee
# it starts with chars, and hence will work as a
# bash variable
echo "id$(uuidgen|tr -d '-')";
}
# Generates a new node 'object'
new_node() {
local node_id="$1";
local value="$2";
local left="$3";
local right="$4";
eval "${node_id}set='set'";
eval "set_node_value $node_id $value";
eval "set_node_left $node_id $right";
eval "set_node_right $node_id $right";
}
# Inserts a value into a tree with a root node with identifier '$id'.
# If the node, hence the tree does not exist it creates it.
# If the root node is at the either end of the list you'll reach the
# worst case complexity of O(N), where N is the number of elements in
# the tree. (Average case will be 0(logN).)
tree_insert() {
local id="$1"
local value="$2";
# If id does not exist, create it
if [ -z "$(eval "echo \$${id}set")" ]; then
eval "new_node $id $value";
# If id exists and the value inserted is less than or equal to
# the id's node's value.
# - Go down the left branch
elif [[ $value -le $(${id}.getValue) ]]; then
# Go down to an existing left node if it exists, otherwise
# create it.
if [ "$(eval ${id}.getLeftChild)xxx" != "xxx" ]; then
tree_insert $(eval ${id}.getLeftChild) $value
else
local uid=$(gen_uid);
tree_insert $uid $value;
set_node_left $id $uid;
fi
# Else go down the right branch as the value inserted is larger
# than the id node's value.
else
# Go down the right node if it exists, else create it
if [ "$(eval ${id}.getRightChild)xxx" != "xxx" ]; then
tree_insert $(eval ${id}.getRightChild) $value
else
local uid=$(gen_uid);
tree_insert $uid $value;
set_node_right $id $uid;
fi
fi
}
# Insert an unsorted list of numbers into a binary search tree
for i in 10 4 16 1 7 12; do
tree_insert bst $i;
done
# Print the binary search tree out in order
print_binary_search_tree bst
Actually, I think, it's super easy to implement aa BST in BASH.
How:
Just create a :) damn .txt :) FILE for maintaining the BST.
Here, I'm not going to show how you can implement the CRUD operation for inserting/populating or deleting/updating a BST nodes if implemented using a simple .txt file, but it works as far as printing values. I'll work on it and share the solution soon.
Here is my solution: Just FYSA In BASH, I used a .txt file approach and tried for printing the same from any root node here: https://stackoverflow.com/a/67341334/1499296