
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
On a rectangular chessboard filled with chess pieces, two players, A and B, take turns removing chess pieces. The rule is: in any row or column, take any number of consecutive pieces (i.e., pieces cannot be taken from non-adjacent spots). A turn cannot be skipped, and pieces cannot be taken from multiple rows or columns at once. The game ends when all pieces are removed from the chessboard. The player who takes the last piece wins.

Given the chessboard as shown in the diagram, the first player can guarantee a win. What should the first player do on their first move to ensure a win? (List all correct strategies).

Present the answer in LaTex format: \boxed{Your answer}
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