c++ the hash function with 31 const

The hash function in C++ with 31 const is a commonly used algorithm to convert a given input into a unique numerical value. The steps involved in this hash function are as follows:

1. Initialize a variable, let's call it 'hash', to an initial value of 0.

2. Iterate over each character in the input string.

3. For each character, multiply the current hash value by 31 and add the ASCII value of the character to it.

4. After iterating over all the characters, return the final hash value.

The reason behind using the constant value of 31 in this hash function is that it is a prime number. Prime numbers are often chosen for hash functions because they tend to produce a more even distribution of hash values.

Using 31 as the constant multiplier helps to avoid collisions, where different inputs produce the same hash value. This is because multiplying by a prime number helps to spread out the values across a wider range.

Overall, this hash function with a constant value of 31 is a simple and effective way to generate unique hash values for different inputs in C++.