Bird
Raised Fist0

Which algorithmic approach guarantees an optimal solution for this problem?

easy🔍 Pattern Recognition Q11 of Q15
Tree: Depth-First Search - Path Sum
You are given a binary tree and a target sum. You need to determine if there exists a root-to-leaf path such that adding up all the values along the path equals the target sum. Which algorithmic approach guarantees an optimal solution for this problem?
ADepth-first search (DFS) with early stopping upon finding a valid path
BGreedy traversal choosing the child with the closest value to the target sum
CDynamic programming with memoization of partial sums at each node
DBreadth-first search (BFS) exploring all paths level by level
Step-by-Step Solution

  1. Step 1: Understand the problem constraints

    The problem requires checking if any root-to-leaf path sums to the target. This naturally fits a tree traversal pattern.

  2. Step 2: Identify the best approach

    DFS with early stopping is optimal because it explores paths deeply and stops as soon as a valid path is found, avoiding unnecessary work.

  3. Final Answer:

    Option A -> Option A

  4. Quick Check:

    DFS explores paths fully and stops early when possible [OK]
Quick Trick: Early stopping DFS avoids unnecessary traversal [OK]
Common Mistakes:
MISTAKES
  • Believing greedy approach works for sums
  • Confusing BFS with DFS for path sums
Trap Explanation:
PITFALL
  • BFS explores all nodes at each level, which is less efficient here; greedy fails because local choices don't guarantee global sum.
Interviewer Note:
CONTEXT
  • Tests if candidate can recognize the correct traversal pattern for path sum problems.
Master "Path Sum" in Tree: Depth-First Search

3 interactive learning modes - each teaches the same concept differently

Try ItSolutionTrace

Want More Practice?

15+ quiz questions · All difficulty levels · Free

Free Signup - Practice All Questions
More Tree: Depth-First Search Quizzes
Binary Tree Cameras - Binary Tree Cameras - Quiz 15hard Binary Tree Cameras - Binary Tree Cameras - Quiz 1easy Binary Tree Inorder Traversal - Binary Tree Inorder Traversal - Quiz 14medium Binary Tree Preorder Traversal - Binary Tree Preorder Traversal - Quiz 15hard Construct Tree from Inorder and Postorder - Construct Tree from Inorder and Postorder - Quiz 9hard Construct Tree from Inorder and Postorder - Construct Tree from Inorder and Postorder - Quiz 5medium Flatten Binary Tree to Linked List - Flatten Binary Tree to Linked List - Quiz 8hard Lowest Common Ancestor of Binary Tree - Lowest Common Ancestor of Binary Tree - Quiz 1easy Sum Root to Leaf Numbers - Sum Root to Leaf Numbers - Quiz 8hard Symmetric Tree (DFS Approach) - Symmetric Tree (DFS Approach) - Quiz 3easy