Python/graphs/dijkstra_2.py

def printDist(dist, V):
    print("\nVertex Distance")
    for i in range(V):
        if dist[i] != float("inf"):
            print(i, "\t", int(dist[i]), end="\t")
        else:
            print(i, "\t", "INF", end="\t")
        print()


def minDist(mdist, vset, V):
    minVal = float("inf")
    minInd = -1
    for i in range(V):
        if (not vset[i]) and mdist[i] < minVal:
            minInd = i
            minVal = mdist[i]
    return minInd


def Dijkstra(graph, V, src):
    mdist = [float("inf") for i in range(V)]
    vset = [False for i in range(V)]
    mdist[src] = 0.0

    for i in range(V - 1):
        u = minDist(mdist, vset, V)
        vset[u] = True

        for v in range(V):
            if (
                (not vset[v])
                and graph[u][v] != float("inf")
                and mdist[u] + graph[u][v] < mdist[v]
            ):
                mdist[v] = mdist[u] + graph[u][v]

    printDist(mdist, V)


if __name__ == "__main__":
    V = int(input("Enter number of vertices: ").strip())
    E = int(input("Enter number of edges: ").strip())

    graph = [[float("inf") for i in range(V)] for j in range(V)]

    for i in range(V):
        graph[i][i] = 0.0

    for i in range(E):
        print("\nEdge ", i + 1)
        src = int(input("Enter source:").strip())
        dst = int(input("Enter destination:").strip())
        weight = float(input("Enter weight:").strip())
        graph[src][dst] = weight

    gsrc = int(input("\nEnter shortest path source:").strip())
    Dijkstra(graph, V, gsrc)