Codeforces Beta Round 99 (Div. 1)
D
World of Darkraft
Codeforces
2500
原题
← CE →
翻译中…

Recently Roma has become the happy owner of a new game World of Darkraft. This game combines elements of virtually all known genres, and on one of the later stages of the game Roma faced difficulties solving a puzzle.

翻译中…

In this part Roma fights with a cunning enemy magician. The battle takes place on a rectangular field plaid $*n* × *m*$. Each cell contains one magical character: L, R or X. Initially all the squares of the field are "active".

翻译中…

The players, Roma and enemy magician, take turns. Roma makes the first move. During a move a player selects one of the active cells. Then depending on the image in the character in the cell one of the following actions takes place:

翻译中…
  • L — magical waves radiate from the cell to the left downwards and to the right upwards along diagonal paths. All cells on the path of the waves (including the selected cell too) become inactive. The waves continue until the next inactive cell or to the edge of the field if there are no inactive cells on the way.
  • R — the magical waves radiate to the left upwards and to the right downwards.
  • X — the magical waves radiate in all four diagonal directions.
翻译中…

If the next player cannot make a move (i.e., all cells are inactive), he loses.

翻译中…

Roma has been trying to defeat the computer opponent for three days but he just keeps losing. He asks you to help him and determine whether it is guaranteed that he can beat the opponent, or he will have to hack the game.

翻译中…

Input

翻译中…

The first line contains two space-separated integers $*n*$ and $*m*$ ($1 ≤ *n*, *m* ≤ 20$).

翻译中…

Next $*n*$ lines contain $*m*$ characters describing the playing field: the $*j*$-th character of the $*i*$-th line equals to the magical character of the corresponding field square.

翻译中…

Output

翻译中…

On the first line print "WIN" if Roma can win or "LOSE" if it is impossible to win considering that the opponent pays optimally.

翻译中…

Note

翻译中…

In the first test each move makes one diagonal line of the square inactive, thus it is guaranteed that Roma loses after two moves.

翻译中…

There are three variants of making a move in the second test: to "finish off" the main diagonal line or any of the squares that are left. That means that after three moves the game stops and Roma wins.

翻译中…

样例

Input #1
2 2
RL
LR
Output #1
LOSE
InputCopy OutputCopy
Input #2
2 2
RR
RR
Output #2
WIN
InputCopy OutputCopy
题目信息
题号
138D
时间限制
2 s
内存限制
256 MB
标签
动态规划
博弈论

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。