What is the time complexity of dijkstra's algorithm?

Worst case O((V + E) log V). Space complexity is O(V). Fails on negative weights: a settled node can turn out to be wrong.

Dijkstra's algorithm

medium

When a node comes off the priority queue it is final - no unexplored route can beat it. Set an edge weight negative to watch that greedy argument fail.

Worst O((V + E) log V)Space O(V)

Loading the dijkstra's algorithm engine…

Where to go next

Bellman-Ford

medium

Slower than Dijkstra, but it survives negative weights.

Prim's algorithm

medium

Dijkstra with one line changed.

A* and BFS pathfinding

medium

Paint a maze and watch three algorithms solve it differently.