da = [1, 9] db = [10, 19] dc = [1, 10] dd = [dc, [2, 10]] diff = {"+": [[da] * 2, [db, da], [db, da], [db] * 2], "-": [[da] * 2, [db, da], [[10, 20], [10, 20]], [db] * 2], "*": [[dc] * 2, [dc] * 2, [[2, 10], [11, 20]], [[1, 25], [1, 25]]], "/": [dd, dd, dd, [[1, 20], [2, 20]]]}