Two Merchants

There are two merchants in the market. Initially, the first merchant has $N$ items for sale at **distinct** prices $A_1, A_2, \ldots, A_N$ and the second merchant has $M$ items for sale at **distinct** prices $B_1, B_2, \ldots, B_M$. If you buy an item from a merchant, the prices of all remaining items for both merchants change in the following manner: - The cost of all the remaining items of th