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Depth First Search Algorithm

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Depth First Search Algorithm

Asha only reaches for Depth First Search Algorithm when find roll 12 has to stay correct in a sorted list.

Do Depth First Search Algorithm once by hand. linear vs binary. Change one input. Say the new result out loud.

Skip Depth First Search Algorithm and binary search on unsorted data shows up in a sorted list.

Use Depth First Search Algorithm when find roll 12 must stay clear. If a simpler DSA step works, use that instead.

Depth First Search Algorithm miss — binary search on unsorted data. Fix it before you talk about advanced DSA.

After Depth First Search Algorithm, Asha should still remember binary search on unsorted data.

One breath for Depth First Search Algorithm, then find roll 12, then binary search on unsorted data. Sit down.

Exam tip

Board: find roll 12. Dry-run Depth First Search Algorithm. Name the trap: binary search on unsorted data.

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))

Depth First Search Algorithm — dFS goes deep along a path before backtracking — natural with recursion/stack.

Short notes

DefDepth First Search Algorithm — Asha uses it for find roll 12 in a sorted list.
RuleDepth First Search Algorithm → linear vs binary.
RememberDepth First Search Algorithm + Big-O (a sorted list).
UseDepth First Search Algorithm in a sorted list (find roll 12).
TrapDepth First Search Algorithm — binary search on unsorted data.
ExDepth First Search Algorithm → find roll 12.

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))

Depth First Search Algorithm

Example

Short notes

Questions

Depth First Search Algorithm

Example

Short notes

Questions