def topological_sort(graph):

    is_visit = dict((node,False) for node in graph )
    order = []
    count = 0

    def dfs(graph,start_node):

        for end_node in graph[start_node]:
            if not is_visit[end_node]:
                is_visit[end_node] = True
                dfs(graph,end_node)
        order.append(start_node)

    for start_node in graph:
        if not is_visit[start_node]:
            is_visit[start_node] = True
            dfs(graph,start_node)
            order.append(" ")
    return order

def read_file():
    list1 = []
    f = open("list.txt","r")
    line = f.readline()
    while line:
        line = line.split(',')
        for index,item in enumerate(line):
            line[index] = eval(item)
        list1.append(line)
        line = f.readline()
    f.close()
    dict1 ={}
    for k,v in enumerate(list1):
        dict1[k] =v
    return dict1

def main():
    graph = read_file()
    order_list = topological_sort(graph)
    f = open("dfs.txt","w")
    i = 0
    count = 0
    while i < len(order_list):
        if order_list[i] == " ":
            f.write("\n")
            count +=1
        else:
            f.write(str(i-count)+","+str(order_list[i]))
            f.write("\n")
        i+=1
    f.close()

main()