Gangsters

You live in a graph G, with N vertices and M edges. P of these vertices have gangsters living on them. You owe each gangster some money, given by the array C (of size P). You wish to travel from s to t. If you step within distance k of any gangster who you haven't paid, you die. We define the length of a path as then number of edges it comprises. We define the distance of two nodes as the length