DSA · Theory

Detect Cycle in Graph using DSU

Theory

521/810

Detect Cycle in Graph using DSU

If you can teach Detect Cycle in Graph using DSU using bus routes, you know it. If you only know the heading, you don’t.

For Detect Cycle in Graph using DSU, Big-O is in play. Don’t blame it until you have traced bus routes.

Skip Detect Cycle in Graph using DSU and no visited set → infinite loop shows up in a city map.

Use Detect Cycle in Graph using DSU when bus routes must stay clear. If a simpler DSA step works, use that instead.

If bus routes breaks under Detect Cycle in Graph using DSU, check no visited set → infinite loop first.

After Detect Cycle in Graph using DSU, Meera should still remember no visited set → infinite loop.

One breath for Detect Cycle in Graph using DSU, then bus routes, then no visited set → infinite loop. Sit down.

Exam tip

Say Detect Cycle in Graph using DSU in one breath, then BFS queue / DFS stack, then no visited set → infinite loop.

Example

# adjacency list
graph = {
    "A": [("B", 2), ("C", 5)],
    "B": [("A", 2), ("C", 1)],
    "C": [("A", 5), ("B", 1)],
}
for u, edges in graph.items():
    print(u, "->", edges)

Detect Cycle in Graph using DSU — graphs are often stored as adjacency lists: vertex → list of (neighbor, weight).

Short notes

DefDetect Cycle in Graph using DSU — Meera uses it for bus routes in a city map.
RuleDetect Cycle in Graph using DSU → BFS queue / DFS stack.
RememberDetect Cycle in Graph using DSU + Big-O (a city map).
UseDetect Cycle in Graph using DSU in a city map (bus routes).
TrapDetect Cycle in Graph using DSU — no visited set → infinite loop.
ExDetect Cycle in Graph using DSU → bus routes.

DSA · Theory

Detect Cycle in Graph using DSU

← All stacks

Theory

521/810

Detect Cycle in Graph using DSU

If you can teach Detect Cycle in Graph using DSU using bus routes, you know it. If you only know the heading, you don’t.

For Detect Cycle in Graph using DSU, Big-O is in play. Don’t blame it until you have traced bus routes.

Skip Detect Cycle in Graph using DSU and no visited set → infinite loop shows up in a city map.

Use Detect Cycle in Graph using DSU when bus routes must stay clear. If a simpler DSA step works, use that instead.

If bus routes breaks under Detect Cycle in Graph using DSU, check no visited set → infinite loop first.

After Detect Cycle in Graph using DSU, Meera should still remember no visited set → infinite loop.

One breath for Detect Cycle in Graph using DSU, then bus routes, then no visited set → infinite loop. Sit down.

Exam tip

Say Detect Cycle in Graph using DSU in one breath, then BFS queue / DFS stack, then no visited set → infinite loop.

Example

# adjacency list
graph = {
    "A": [("B", 2), ("C", 5)],
    "B": [("A", 2), ("C", 1)],
    "C": [("A", 5), ("B", 1)],
}
for u, edges in graph.items():
    print(u, "->", edges)

Detect Cycle in Graph using DSU — graphs are often stored as adjacency lists: vertex → list of (neighbor, weight).

Short notes

DefDetect Cycle in Graph using DSU — Meera uses it for bus routes in a city map.
RuleDetect Cycle in Graph using DSU → BFS queue / DFS stack.
RememberDetect Cycle in Graph using DSU + Big-O (a city map).
UseDetect Cycle in Graph using DSU in a city map (bus routes).
TrapDetect Cycle in Graph using DSU — no visited set → infinite loop.
ExDetect Cycle in Graph using DSU → bus routes.

Detect Cycle in Graph using DSU

Example

Short notes

Questions

Detect Cycle in Graph using DSU

Example

Short notes

Questions