We define illegal edges as edges that are traversed in reverse. Suppose there is an edge from a-->b but you wanna traverse it in the opposite direction b-->a regardless of the fact that there is no edge b-->a, that becomes an illegal edge.

Give a linear-time algorithm that computes a path from s to t that minimizes the number of illegal edges given a directed graph G and locations s and t as input using Dijkstra's algorithm.

Hint: solve this by reduction to a standard single-source shortest path problem.