What type of data do hash functions use to return results in a map container?

In Go, hash functions used for keys in a map container return a value of type uint64 (a 64-bit unsigned integer). This value serves as an index for quick lookup of the corresponding value in the map.

It is important to note that in Go, map keys can only be types that support comparison (e.g., strings, numbers, pointers, structs with comparable fields). Internally, hashing of keys is used for access optimization, and the result is an integer value.

Therefore, the data type returned by the hash function for a map key is an unsigned integer, usually uint64.