yukicoder No.3 ビットすごろく

やっと解けたぜ！ヾ(oﾟωﾟo)ﾉﾞ
ここまで長かった…

from collections import deque

N = int(input())

que = deque([1])
now = 1
visited = [False for i in range(N+1)]
step = [-1 for i in range(N+1)]
visited[1] = True
step[1] = 1
step_count = 1

while len(que) > 0:
    now = que.popleft()
    step_count = step[now] + 1
    step_width = bin(now).count("1")
    next_front = now + step_width
    next_back = now - step_width
    if next_front <= N and visited[next_front] is False:
        que.append(next_front)
        visited[next_front] = True
        step[next_front] = step_count
    if next_back >= 1 and visited[next_back] is False:
        que.append(next_back)
        visited[next_back] = True
        step[next_back] = step_count

if now == N:
    print(step[N])
else:
    print(-1)