from collections import deque def quickestWayUp(ladders, snakes):

graph = {}
for x, y in (ladders + snakes):
    graph[x] = y
visited = [False]*(101) 
q = deque([(1, 0)])
visited[1] = True 
while q:
    node, roll = q.popleft()
    if node == 100:
        return roll   
    visited[node] = True
    for i in range(1, 7):
        nodeNext = node + i
        if  nodeNext <= 100 and visited[nodeNext] == False:
            if nodeNext in graph:
                q.append(( graph[nodeNext], roll + 1 ))
            else:
                q.append(( nodeNext, roll + 1 ))
return -1