CF226D The table

Harry Potter has a difficult homework. Given a rectangular table, consisting of $ n×m $ cells. Each cell of the table contains the integer. Harry knows how to use two spells: the first spell change the sign of the integers in the selected row, the second — in the selected column. Harry's task is to make non-negative the sum of the numbers in each row and each column using these spells. Alone, the boy can not cope. Help the young magician!

N/A

N/A