n, m = map(int, input().split())

mat = [list(map(int, input().split())) for _ in range(n)]

dist = [[float('inf')] * m for _ in range(n)]
dist[0][0] = 0

q = [(0, 0)]
while q:
    nq = []
    for x, y in q:
        for dx, dy in zip((-1, 0, 1, 0), (0, -1, 0, 1)):
            nx, ny = x + dx, y + dy
            if nx == n - 1 and ny == m - 1: print(dist[x][y] + 1); exit(0)
            if 0 <= nx < n and 0 <= ny < m and mat[nx][ny] == 0 and dist[nx][ny] > dist[x][y] + 1:
                dist[nx][ny] = dist[x][y] + 1
                nq.append((nx, ny))
    q = nq