DFS.py

class Vertex:
    def __init__(self,key):
        self.id=key
        self.connectedTo={}
    
    def addNeighbor(self,nbr,weight=0):
        self.connectedTo[nbr]=weight
    
    def __str__(self):
        return str(self.id)+' connectedTo: '+str([x.id for x in self.connectedTo])
    
    def getConnections(self):
        return self.connectedTo.keys()
    
    def getId(self):
        return self.id
    
    def getWeight(self,nbr):
        return self.connectedTo[nbr]
    
class Graph:
    def __init__(self):
        self.vertList={}
        self.numVertices=0
        
    def addVertex(self,key):
        self.numVertices=self.numVertices+1
        newVertex=Vertex(key)
        self.verList[key]=newVertex
        return newVertex
    
    def getVertex(self,n):
        if n in self.vertList:
            return self.vertList[n]
        else:
            return None
    
    def __contains__(self,n):
        return n in self.vertList
    
    def addEdge(self,f,t,cost=0):
        if f not in self.vertList:
            nv = self.addVertex(f)
        if t not in self.vertList:
            nv = self.addVertex(t)
        self.vertList[f].addNeighbor(self,vertList[t],cost)
        
    def getVertices(self):
        return self.vertList.keys()
    
    def __iter__(self):
        return iter(self.vertList.values())