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Difference between BFS and DFS

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Difference between BFS and DFS

Difference between BFS and DFS is a DSA idea you prove with bus routes, not with a slogan.

Do Difference between BFS and DFS once by hand. BFS queue / DFS stack. Change one input. Say the new result out loud.

Difference between BFS and DFS exists so Arun can keep bus routes correct in a city map.

Difference between BFS and DFS shows up in a city map. Name bus routes, not “a real-world scenario”.

If bus routes breaks under Difference between BFS and DFS, check no visited set → infinite loop first.

Difference between BFS and DFS is not a lonely heading. Arun ties it to bus routes.

Close Difference between BFS and DFS with: “If I skip it, bus routes goes wrong like this: no visited set → infinite loop.”

Exam tip

For Difference between BFS and DFS: definition + a city map + one failure.

Example

from collections import deque

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

def bfs(start):
    seen, q = {start}, deque([start])
    order = []
    while q:
        u = q.popleft()
        order.append(u)
        for v in graph[u]:
            if v not in seen:
                seen.add(v)
                q.append(v)
    return order

print(bfs(1))

Difference between BFS and DFS — bFS explores level by level using a queue.

Short notes

DefDifference between BFS and DFS — Arun uses it for bus routes in a city map.
RuleDifference between BFS and DFS → BFS queue / DFS stack.
RememberDifference between BFS and DFS + a dry-run table (a city map).
UseDifference between BFS and DFS in a city map (bus routes).
TrapDifference between BFS and DFS — no visited set → infinite loop.
ExDifference between BFS and DFS → bus routes.

from collections import deque graph = {1: [2, 3], 2: [4], 3: [], 4: []} def bfs(start): seen, q = {start}, deque([start]) order = [] while q: u = q.popleft() order.append(u) for v in graph[u]: if v not in seen: seen.add(v) q.append(v) return order print(bfs(1))

Difference between BFS and DFS

Example

Short notes

Questions

Difference between BFS and DFS

Example

Short notes

Questions