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DFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List

Theory

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DFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List

If you can teach DFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List using folder on disk, you know it. If you only know the heading, you don’t.

DFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List order: meaning → left < root < right → one limit. Dumping ten features helps nobody.

Without DFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List, a file explorer gets messy and folder on disk is hard to trust.

Sara ships DFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List in a file explorer. That is the use case worth saying.

Don’t do this with DFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List: unbalanced BST becoming a list. Interviewers spot it in ten seconds.

DFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List is not a lonely heading. Sara ties it to folder on disk.

One breath for DFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List, then folder on disk, then unbalanced BST becoming a list. Sit down.

Exam tip

For DFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List: definition + a file explorer + one failure.

Example

graph = {1: [2, 3], 2: [4], 3: [], 4: []}

def dfs(u, seen=None):
    if seen is None:
        seen = set()
    seen.add(u)
    order = [u]
    for v in graph[u]:
        if v not in seen:
            order += dfs(v, seen)
    return order

print(dfs(1))

DFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List — dFS goes deep along a path before backtracking — natural with recursion/stack.

Short notes

DefDFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List — Sara uses it for folder on disk in a file explorer.
RuleDFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List → left < root < right.
RememberDFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List + Big-O (a file explorer).
UseDFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List in a file explorer (folder on disk).
TrapDFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List — unbalanced BST becoming a list.
ExDFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List → folder on disk.

graph = {1: [2, 3], 2: [4], 3: [], 4: []} def dfs(u, seen=None): if seen is None: seen = set() seen.add(u) order = [u] for v in graph[u]: if v not in seen: order += dfs(v, seen) return order print(dfs(1))

DFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List

Example

Short notes

Questions

DFS for an n-ary Tree(Acyclic Graph) Represented as an Adjacency List

Example

Short notes

Questions