For an n×mn times mn×m grid which is fully covered by 1×21 times 21×2 and 2×12 times 12×1 domnios, Bobo can perform the following two kinds of operations. * Choose a 2×22 times 22×2 subgrid which is covered by two 1×21 times 21×2 domnios, replace the two domnios with two 2×12 times 12×1 ones. * Choose a 2×22 times 22×2 subgrid which is covered by two 2×12 times 12×1 domnios, replace the two domnios with two 1×21 times 21×2 ones. Bobo has two n×mn times mn×m grids which are fully covered by domnios. He would like to know the minimum number of operations to make them identical.
For an n×mn times mn×m grid which is fully covered by 1×21 times 21×2 and 2×12 times 12×1 domnios, Bobo can perform the following two kinds of operations. * Choose a 2×22 times 22×2 subgrid which is covered by two 1×21 times 21×2 domnios, replace the two domnios with two 2×12 times 12×1 ones. * Choose a 2×22 times 22×2 subgrid which is covered by two 2×12 times 12×1 domnios, replace the two domnios with two 1×21 times 21×2 ones. Bobo has two n×mn times mn×m grids which are fully covered by domnios. He would like to know the minimum number of operations to make them identical.
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