What are the main disadvantages that can arise when using hash functions?

Main disadvantages of using hash functions:

• Collisions: different input data can produce the same hash, which requires additional handling (for example, in hash tables).
• Security vulnerabilities: some hash functions may be susceptible to attacks (such as collisions or prediction) if they are not cryptographically secure.
• Irreversibility: hash functions are irreversible, so it is impossible to recover the original data from the hash, which sometimes limits their application.
• Performance: complex hash functions can be resource-intensive, affecting processing speed.

In iOS, when using hash functions, it is important to choose an appropriate algorithm and consider possible collisions and security.