摘要： Vasya has the square chessboard of size n × n and m rooks. Initially the chessboard is empty. Vasya will consequently put the rooks on the board one a 阅读全文

摘要： DZY loves chessboard, and he enjoys playing with it. He has a chessboard of n rows and m columns. Some cells of the chessboard are bad, others are goo 阅读全文