Challenges Implementing Dijkstra's Algorithm in Go - Incorrect Shortest Path Results
I'm working on a personal project and I've looked through the documentation and I'm still confused about I'm sure I'm missing something obvious here, but I'm having trouble implementing Dijkstra's algorithm in Go for finding the shortest path in a weighted graph. My current implementation is returning incorrect results for some graphs, particularly those with higher edge weights. For example, with the graph below, the shortest path from node A to node D should be A -> C -> D with a total weight of 3, but I'm getting a total weight of 5 instead. Here’s a simplified version of my code: ```go package main import ( "container/heap" "fmt" ) type Edge struct { to string weight int } type Graph map[string][]Edge type Item struct { node string cost int } type PriorityQueue []*Item func (pq PriorityQueue) Len() int { return len(pq) } func (pq PriorityQueue) Less(i, j int) bool { return pq[i].cost < pq[j].cost } func (pq PriorityQueue) Swap(i, j int) { pq[i], pq[j] = pq[j], pq[i] } func (pq *PriorityQueue) Push(x interface{}) { item := x.(*Item) *pq = append(*pq, item) } func (pq *PriorityQueue) Pop() interface{} { old := *pq n := len(old) item := old[n-1] *pq = old[0 : n-1] return item } func Dijkstra(graph Graph, start string) map[string]int { dist := make(map[string]int) for node := range graph { dist[node] = int(^uint(0) >> 1) // Set to infinity } dist[start] = 0 pq := &PriorityQueue{&Item{start, 0}} heap.Init(pq) for pq.Len() > 0 { curr := heap.Pop(pq).(*Item) for _, edge := range graph[curr.node] { newDist := curr.cost + edge.weight if newDist < dist[edge.to] { dist[edge.to] = newDist heap.Push(pq, &Item{edge.to, newDist}) } } } return dist } func main() { graph := Graph{ "A": {{"B", 1}, {"C", 4}}, "B": {{"C", 2}, {"D", 5}}, "C": {{"D", 1}}, "D": {}, } result := Dijkstra(graph, "A") fmt.Println(result) } ``` When I run this code, I receive the output: ``` map[A:0 B:1 C:3 D:5] ``` While this seems correct at first glance, I suspect the logic in my priority queue or how I update the distances might be flawed. I’ve also tried using different graph configurations and edge weights to confirm the issue persists. Any insights on what I might be overlooking, especially related to Go's handling of pointers with the priority queue or potential issues with the graph structure itself? Thanks! For context: I'm using Go on Linux. My team is using Go for this mobile app. Could this be a known issue? Could this be a known issue? Thanks for taking the time to read this! Am I approaching this the right way?