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320 Chap. 9 Searching01000953012330134567987720071057899879Figure 9.3 An illustration of open hashing for seven numbers stored in a ten-slothash table using the hash function h(K) = K mod 10. The numbers are insertedin the order 9877, 2007, 1000, 9530, 3013, 9879, and 1057. Two of the valueshash to slot 0, one value hashes to slot 2, three of the values hash to slot 7, andone value hashes to slot 9.the sum for the integer quantities will typically cause a 32-bit integer tooverflow (thus losing some of the high-order bits) because the resultingvalues are so large. But this causes no problems when the goal is to computea hash function.9.4.2 Open HashingWhile the goal of a hash function is to minimize collisions, some collisions areunavoidable in practice. Thus, hashing implementations must include some form ofcollision resolution policy. Collision resolution techniques can be broken into twoclasses: open hashing (also called separate chaining) and closed hashing (alsocalled open addressing). 3 The difference between the two has to do with whethercollisions are stored outside the table (open hashing), or whether collisions resultin storing one of the records at another slot in the table (closed hashing). Openhashing is treated in this section, and closed hashing in Section 9.4.3.The simplest form of open hashing defines each slot in the hash table to bethe head of a linked list. All records that hash to a particular slot are placed onthat slot’s linked list. Figure 9.3 illustrates a hash table where each slot stores onerecord and a link pointer to the rest of the list.3 Yes, it is confusing when “open hashing” means the opposite of “open addressing,” but unfortunately,that is the way it is.