{"problem":{"name":"Zebraness","description":{"content":"We have a grid with $N$ horizontal rows and $N$ vertical columns.   Let $(i, j)$ denote the square at the $i$\\-th row from the top and $j$\\-th column from the left. A character $c_{i,j}$ describes the","description_type":"Markdown"},"platform":"AtCoder","limit":{"time_limit":2000,"memory_limit":262144},"difficulty":"None","is_remote":true,"is_sync":true,"sync_url":null,"sign":"abc193_f"},"statements":[{"statement_type":"Markdown","content":"We have a grid with $N$ horizontal rows and $N$ vertical columns.  \nLet $(i, j)$ denote the square at the $i$\\-th row from the top and $j$\\-th column from the left. A character $c_{i,j}$ describes the color of $(i, j)$.  \n`B` means the square is painted black; `W` means the square is painted white; `?` means the square is not yet painted.\nTakahashi will complete the black-and-white grid by painting each unpainted square black or white.  \nLet the **zebraness** of the grid be the number of pairs of a black square and a white square sharing a side.  \nFind the maximum possible zebraness of the grid that Takahashi can achieve.\n\n## Constraints\n\n*   $1 ≤ N ≤ 100$\n*   $c_{i, j}$ is `B`, `W`, or `?`.\n\n## Input\n\nInput is given from Standard Input in the following format:\n\n$N$\n$c_{1,1} \\dots c_{1,N}$\n$\\hspace{20pt}\\vdots$\n$c_{N,1} \\dots c_{N,N}$\n\n[samples]","is_translate":false,"language":"English"}],"meta":{"iden":"abc193_f","tags":[],"sample_group":[["2\nBB\nBW","2\n\nWe have two pairs of a black square and a white square sharing a side: $(1, 2), (2, 2)$ and $(2, 1), (2, 2)$, so the zebraness of this grid is $2$."],["3\nBBB\nBBB\nW?W","4\n\nPainting $(3, 2)$ white makes the zebraness $3$, and painting it black makes the zebraness $4$."],["5\n?????\n?????\n?????\n?????\n?????","40"]],"created_at":"2026-03-03 11:01:14"}}