What are some advanced algorithms in C#?

What are some advanced algorithms in C#?

Some advanced algorithms in C# include Dijkstra's algorithm for shortest paths, A* search algorithm, and various sorting algorithms like quicksort and mergesort.

Can you explain Dijkstra's algorithm?

Dijkstra's algorithm finds the shortest path from a starting node to all other nodes in a graph. It uses a priority queue to explore the nearest unvisited node.

How can I implement it in C#?

You can implement Dijkstra's algorithm in C# using a priority queue and a dictionary to track distances. Would you like a code example?

Yes, please provide a code example.

Here's a simple implementation:

using System;
using System.Collections.Generic;

class Graph {
    private Dictionary<int, List<(int, int)>> adjList = new Dictionary<int, List<(int, int)>>();

    public void AddEdge(int source, int destination, int weight) {
        if (!adjList.ContainsKey(source)) adjList[source] = new List<(int, int)>();
        adjList[source].Add((destination, weight));
    }

    public void Dijkstra(int start) {
        var distances = new Dictionary<int, int>();
        var priorityQueue = new SortedSet<(int distance, int node)>();

        foreach (var node in adjList.Keys) {
            distances[node] = int.MaxValue;
        }
        distances[start] = 0;
        priorityQueue.Add((0, start));

        while (priorityQueue.Count > 0) {
            var (currentDistance, currentNode) = priorityQueue.Min;
            priorityQueue.Remove(priorityQueue.Min);

            foreach (var (neighbor, weight) in adjList[currentNode]) {
                var newDist = currentDistance + weight;
                if (newDist < distances[neighbor]) {
                    distances[neighbor] = newDist;
                    priorityQueue.Add((newDist, neighbor));
                }
            }
        }

        foreach (var pair in distances) {
            Console.WriteLine($"Distance from {start} to {pair.Key} is {pair.Value}");
        }
    }
}

This code sets up a graph and implements Dijkstra's algorithm.