Dijkstra's Algorithm

## How Dijkstra's Algorithm Works

Dijkstra's algorithm finds the shortest path from a source node to all other nodes in a weighted graph with non-negative edge weights.

### Algorithm Steps:
1. Set distance to source = 0, all others = infinity
2. Add all nodes to unvisited set
3. While unvisited set is not empty:
- Select node with minimum distance
- For each neighbor, calculate new distance through current node
- Update if new distance is shorter
4. Repeat until all nodes are visited

### Key Characteristics:
- **Greedy**: Always picks the closest unvisited node
- **Optimal**: Guarantees shortest path
- **Non-negative weights only**: Doesn't work with negative edges