How can I optimize the std::hash function in C++11?

How can I optimize the std::hash function in C++11?

To optimize std::hash in C++11, consider using a custom hash function that reduces collisions and improves performance.

What are some common techniques for reducing hash collisions?

Common techniques include using a better seed value, combining multiple hash functions, and ensuring a uniform distribution of input.

Can you provide an example of a custom hash function?

Sure! Here's a simple example:

struct CustomHash {
    std::size_t operator()(const std::string& key) const {
        std::size_t hash = 0;
        for (char c : key) {
            hash = hash * 31 + c;
        }
        return hash;
    }
};

How does this custom hash function compare to std::hash?

This custom hash function can be more efficient for specific types of data, especially if it reduces collisions for your use case.