COMPUTER SCIENCE AND ENGINEERING
DATA STRUCTURES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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produces a random value
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guarantees the value is in range
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avoids collisions
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can work on both integers and chars
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Detailed explanation-1: -we use % (modulo) in hashing to calculate remainder of a division(our data % chosen number). if our mod be a prime number which also is our divisor it is more likely that division has a remainder and less numbers has same factor like our divisor So less collision happens.
Detailed explanation-2: -A good hash function to use with integer key values is the mid-square method. The mid-square method squares the key value, and then takes out the middle r bits of the result, giving a value in the range 0 to 2r−1. This works well because most or all bits of the key value contribute to the result.
Detailed explanation-3: -For hashing, prime numbers are used since they provide a better chance of creating unique values for a hash function.
Detailed explanation-4: -With modular hashing, the hash function is simply h(k) = k mod m for some m (usually, the number of buckets). The value k is an integer hash code generated from the key. If m is a power of two (i.e., m=2p), then h(k) is just the p lowest-order bits of k.