v = input("enter the vertices: ")
v = [x.strip(' ') for x in v.split(',')]



e = input("enter the edges: ")

e = [x.strip(' ') for x in e.split(',')]

graph = list(tuple(x.split('-')) for x in e)

def eulerian_trail(graph):


    first_vertex = graph[0][0]
    adj = {}
    trail = []

    for edge in graph:
        a,b = edge
        if a not in adj:
            adj[a] = []
        if b not in adj:
            adj[b] = []
        adj[a].append(b)
        adj[b].append(a)

    for vertex in v:
        c = vertex
        if c == first_vertex:
            trail.append(c)
            trail.extend(adj[c][0])
            adj.pop([c][0],0)
        if c in trail:
            if adj[c][0] != trail[-1]:
                trail.extend(adj[c][0])
                adj.pop([c][0],0)
            else:
                trail.extend(adj[c][1])
                adj.pop([c][1],0)



    return trail,adj

eulerian_trail(graph)