백준 1697: 숨바꼭질 Python

 

 

from collections import deque


def bfs(v):
    q = deque()
    q.append(v)
    while q:
        v = q.popleft()
        if v == K:
            return visited[v]
        for i in (v-1, v+1, 2*v):
            if 0 <= i <= 100000 and not visited[i]:
                visited[i] = visited[v] + 1
                q.append(i)


N, K = map(int, input().split())
visited = [0] * 100001
print(bfs(N))