Tag: post-order traversal

LeetCode 111. Minimum Depth of Binary Tree in Java

In this post we will solve LeetCode 111. Minimum Depth of Binary Tree problem using Java and the VSCode IDE on a Windows computer. Not that it matters, but I am using Windows 11.

Given a binary tree, find its minimum depth.

The minimum depth is the number of nodes along the shortest path 
from the root node down to the nearest leaf node.

Note: A leaf is a node with no children.

Constraints:

o The number of nodes in the tree is in the range [0, 10^5].
o -1000 <= Node.val <= 1000

Related Topics:

o Tree
* Depth-First Search
* Breadth-First Search
o Binary Tree

We are given the root of a binary tree and are asked to find the minimum depth of the tree. A couple years ago we solved in this post Maximum Depth of a Binary Tree.

The definition of minimum depth is provided in the requirements for the problem at hand. Continue reading “LeetCode 111. Minimum Depth of Binary Tree in Java”

Find Leaf Nodes in a Tree for which the Sum of the Root Path Matches a Target Value

I did not find this problem on a website. The requirements came up during a conversation with a software engineer. I wish I could have taken some notes but I did not. The problem had a single diagram of a sample general tree and there was no class definition for the nodes.

We are given a general binary three in which a node may have none, one or more children.
In addition each node has an integer value.
The values may repeat.

Our tasks if to come up with a function 
that will display the leaf nodes 
for which the sum of all node values in the path from the root 
add up to a defined target.

As far as I can remember that was the gist of the problem. Continue reading “Find Leaf Nodes in a Tree for which the Sum of the Root Path Matches a Target Value”