[Solved] You are given a binary tree and a target sum. The task is to find all root-to-leaf paths where the sum of the node values... Which algorithmic approach guarantees finding all such paths efficiently? | Tree: Depth-First Search

Tree: Depth-First Search - Path Sum II (All Root-to-Leaf Paths)

You are given a binary tree and a target sum. The task is to find all root-to-leaf paths where the sum of the node values equals the target sum. Which algorithmic approach guarantees finding all such paths efficiently?

AGreedy traversal choosing the child with the closest value to the remaining sum

BDepth-first search (DFS) with path tracking and backtracking to explore all root-to-leaf paths

CDynamic programming to store sums at each node and combine results bottom-up

DBreadth-first search (BFS) with queue to find the shortest path matching the sum

Step-by-Step Solution

Solution:

Step 1: Understand problem requires all root-to-leaf paths
Since we must find all paths, not just one, exhaustive exploration is needed.
Step 2: Identify DFS with path tracking and backtracking
DFS explores each path fully, tracking the current path and sum, backtracking to explore alternatives.
Final Answer:
Option B -> Option B
Quick Check:
DFS explores all paths, greedy or BFS do not guarantee all paths [OK]

Quick Trick: All root-to-leaf paths require exhaustive DFS [OK]

Common Mistakes:

MISTAKES

Thinking greedy or BFS finds all paths
Confusing DP for path enumeration

Trap Explanation:

PITFALL

Greedy looks efficient but misses paths; DP bottom-up doesn't track paths explicitly

Interviewer Note:

CONTEXT

Tests if candidate recognizes exhaustive DFS pattern for path enumeration

Master "Path Sum II (All Root-to-Leaf Paths)" in Tree: Depth-First Search

3 interactive learning modes - each teaches the same concept differently

Try It Solution Trace

More Tree: Depth-First Search Quizzes

Which algorithmic approach guarantees finding all such paths efficiently?

Step 1: Understand problem requires all root-to-leaf paths

Step 2: Identify DFS with path tracking and backtracking

Final Answer:

Quick Check:

Want More Practice?