{"problem":{"name":"Advance or Eat","description":{"content":"There is a grid with $N$ rows and $N$ columns, where each square has one white piece, one black piece, or nothing on it.   The square at the $i$\\-th row from the top and $j$\\-th column from the left i","description_type":"Markdown"},"platform":"AtCoder","limit":{"time_limit":2000,"memory_limit":262144},"difficulty":"None","is_remote":true,"is_sync":true,"sync_url":null,"sign":"abc229_h"},"statements":[{"statement_type":"Markdown","content":"There is a grid with $N$ rows and $N$ columns, where each square has one white piece, one black piece, or nothing on it.  \nThe square at the $i$\\-th row from the top and $j$\\-th column from the left is described by $S_{i,j}$. If $S_{i,j}$ is `W`, the square has a white piece; if $S_{i,j}$ is `B`, it has a black piece; if $S_{i,j}$ is `.`, it is empty.\nTakahashi and Snuke will play a game, where the players take alternate turns, with Takahashi going first.\nIn Takahashi's turn, he does one of the following operations.\n\n*   Choose a **white** piece that can move one square up to an empty square, and move it one square up (see below).\n*   Eat a **black** piece of his choice.\n\nIn Snuke's turn, he does one of the following operations.\n\n*   Choose a **black** piece that can move one square up to an empty square, and move it one square up.\n*   Eat a **white** piece of his choice.\n\nThe player who becomes unable to do the operation loses the game. Which player will win when both players play optimally?\nHere, moving a piece one square up means moving a piece at the $i$\\-th row and $j$\\-th column to the $(i-1)$\\-th row and $j$\\-th column.  \nNote that this is the same for both players; they see the board from the same direction.\n\n## Constraints\n\n*   $1 \\leq N \\leq 8$\n*   $N$ is an integer.\n*   $S_{i,j}$ is `W`, `B`, or `.`.\n\n## Input\n\nInput is given from Standard Input in the following format:\n\n$N$\n$S_{1,1}S_{1,2}\\ldots S_{1,N}$\n$S_{2,1}S_{2,2}\\ldots S_{2,N}$\n$\\vdots$\n$S_{N,1}S_{N,2}\\ldots S_{N,N}$\n\n[samples]","is_translate":false,"language":"English"}],"meta":{"iden":"abc229_h","tags":[],"sample_group":[["3\nBB.\n.B.\n...","Takahashi\n\nIf Takahashi eats the black piece at the $1$\\-st row and $1$\\-st columns, the board will become:\n\n.B.\n.B.\n...\n\nThen, Snuke cannot do an operation, making Takahashi win.  \nNote that it is forbidden to move a piece out of the board or to a square occupied by another piece."],["2\n..\nWW","Snuke"],["4\nWWBW\nWWWW\nBWB.\nBBBB","Snuke"]],"created_at":"2026-03-03 11:01:14"}}