सबसे छोटे पथ का पुनर्निर्माण

start = int(input())                    # start vertex
d = [-1] * n                            # distance from start vertex
p = [-1] * n                            # parent vertex
q = deque([start])                      # queue of vertices
d[start] = 0                            # distance from start to start is 0

while q:                                # while the queue is not empty
    v = q.popleft()                     # get vertex from queue
    print(v, end=' ')                   # print vertex
    for to in g[v]:                     # for each vertex connected to v
        if d[to] == -1:                 # if vertex is not visited
            d[to] = d[v] + 1            # (start -> to) = (start -> v) + 1
            p[to] = v                   # parent of vertex is v
            q.append(to)                # add vertex to queue

# Reconstruction of the path from start to end
end = int(input())                      # end vertex
path = []                               # path from start to end
while end != -1:                        # while there is a parent vertex
    path.append(end)                    # add vertex to path
    end = p[end]                        # go to parent vertex

print(*path[::-1], sep=' -> ')          # print the path in reverse order