42 lines
1.0 KiB
Python
42 lines
1.0 KiB
Python
import sys
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from collections import deque
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from collections import defaultdict
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sys.setrecursionlimit(10**6)
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input = sys.stdin.readline
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graph = defaultdict(list)
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n, m = map(int, input().split())
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arr = []
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for i in range(n):
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arr.append(list(map(int, input().strip())))
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dist = [[[0 for _ in range(2)] for _ in range(m)] for _ in range(n)]
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dx = [0, 1, 0, -1]
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dy = [1, 0, -1, 0]
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now_x, now_y = 0, 0
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q = deque([(0, 0, False)])
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dist[0][0][0] = 1
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while q:
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x, y, jump = q.popleft()
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if x == m-1 and y == n-1:
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print(dist[y][x][jump])
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sys.exit(0)
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for dx, dy in ((x+1, y), (x, y+1), (x-1, y), (x, y-1)):
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if 0<=dx<m and 0<=dy<n:
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if arr[dy][dx] == 0 and dist[dy][dx][jump] == 0:
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q.append((dx, dy, jump))
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dist[dy][dx][jump] = dist[y][x][jump] + 1
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elif arr[dy][dx] == 1 and jump == False and dist[dy][dx][1] == 0:
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q.append((dx, dy, True))
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dist[dy][dx][1] = dist[y][x][jump] + 1
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print(-1)
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