How can I implement hashing algorithms in C++11?

How can I implement hashing algorithms in C++11?

You can implement hashing algorithms in C++11 using the standard library's std::hash or by creating your own hash functions. Would you like an example?

Yes, please provide an example of a custom hash function.

Sure! Here's a simple example of a custom hash function for a string:

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

How do I use this hash function with an unordered_map?

You can use it like this:

#include <unordered_map>
#include <string>

std::unordered_map<std::string, int, StringHash> myMap;
myMap["example"] = 1;

What are some common hashing algorithms I should know about?

Some common hashing algorithms include MD5, SHA-1, and SHA-256. Each has its own use cases and security considerations.