In an n*n
grid, there is a snake that spans 2 cells and starts moving
from the top left corner at (0, 0)
and (0, 1)
. The grid has empty
cells represented by zeros and blocked cells represented by ones. The snake wants to reach
the lower right corner at (n-1, n-2)
and (n-1, n-1)
.
In one move the snake can:
(r,
c)
and (r, c+1)
to (r, c)
and (r+1,
c)
.(r, c)
and (r+1,
c)
to (r, c)
and (r, c+1)
.Return the minimum number of moves to reach the target.
If there is no way to reach the target, return -1
.
Example 1:
Input: grid = [[0,0,0,0,0,1], [1,1,0,0,1,0], [0,0,0,0,1,1], [0,0,1,0,1,0], [0,1,1,0,0,0], [0,1,1,0,0,0]] Output: 11 Explanation: One possible solution is [right, right, rotate clockwise, right, down, down, down, down, rotate counterclockwise, right, down].
Example 2:
Input: grid = [[0,0,1,1,1,1], [0,0,0,0,1,1], [1,1,0,0,0,1], [1,1,1,0,0,1], [1,1,1,0,0,1], [1,1,1,0,0,0]] Output: 9
Constraints:
2 <= n <= 100
0 <= grid[i][j] <= 1