MINIMUM DEPTH OF BINARY TREE | LEETCODE # 111 | PYTHON DFS SOLUTION

[@antoinenijhuis450]

Thanks for this video, very insightful breakdown of the question.

[@leeroymlg4692]

Hello everyone welcome back and let's write some more neetcode today

[@crackfaang]

Noooooooo 🙅‍♂️🙅‍♂️

[@antoinenijhuis450]

For a CS Graduate that is not very strong in projects resumé but loves grinding leetcode. Should I focus on projects first before getting into Leetcode 150? Or do you reckon it is useful for me to grind these kind of problems without much programming experience?

[@jaredtewodros]

How can you implement this solution without the global min variable?

[@LawAssistantAI]

n this particular scenario, if we find a leaf node, we could technically stop searching further because we already have a minimum depth candidate. This approach is especially useful in the context of finding the minimum depth of a binary tree. Instead of searching all the nodes unnecessarily, we can stop the search early when we find the first leaf node at the current minimum depth. This would prevent us having to continue to traverse, wouldnt it?

[@Tallonest]

No, because what if you start at the root and find a leaf node on the left subtree 3 down? If you explore the right subtree next, what if you find it’s 1 down? So you actually need to keep going

[@vabhs192003]

Wouldn't the following test case fail for the empty tree such as [], since the default value is set as float('int') while the value returned should be 0?

[@ilhomsadriddinov3627]

Why didn’t you use bfs approach which is slightly better for average cases. I mean traversing the tree by level.

[@crackfaang]

In retrospect I should have used BFS because you can theoretically stop early but in the case of an extremely skewed tree, the overall time complexity is the same. We only care about worst case runtime complexity when doing the analysis so both are fine. You could mention the average case thing for some bonus points but either answer works here as they are the same overall time/space complexity

[@moezzzz9341]

one thing im confused is how you have access to minDepth in your dfs method which is defined in the original method? Is it because you are attaching self to the front of it so both methods have access to that variable?

[@versace10]

hes not calling the method he created a min_depth variable which hes using

[@rishikaverma9846]

ValueError: could not convert string to float: 'int' self.min_depth = float('int') Line 11 in minDepth (Solution.py) ret = Solution().minDepth(param_1) Line 38 in _driver (Solution.py) _driver() Line 49 in (Solution.py) the same code shows this error. can you please tell me how to solve it?

[@crackfaang]

It’s float(‘inf’) not ‘int’. You spelled it wrong 😉

[@leetcoderafeeq2641]

thank you

[@sarayarmohammadi3376]

thank you