Given a graph, find the number of shortest paths present between source and destination?

Question

Given a graph and a source node and destination node, find the number of shortest paths present between source and destination?

Comments

There is an algorithm called as Dijkstra algorithm for finding shortest path from one node to another for a weighted graph (the weight of the graph must be positive), and there is no such things as "number of shortest path", there is only one shortest path from source to destination node.