What are some examples of using hash functions in C++?

What are some examples of using hash functions in C++?

In C++, hash functions are often used in data structures like hash tables. For example, you can use the std::hash template to hash strings or integers.

Can you show me a code snippet for hashing a string?

Sure! Here's a simple example:

#include <iostream>
#include <string>
#include <functional>

int main() {
    std::string str = "Hello, World!";
    std::hash<std::string> hash_fn;
    size_t hash = hash_fn(str);
    std::cout << "Hash of \"" << str << "\" is: " << hash << std::endl;
    return 0;
}

What about using hash functions with custom objects?

You can create a custom hash function by specializing std::hash. Here's an example:

struct Point {
    int x, y;
};

namespace std {
    template <> struct hash<Point> {
        size_t operator()(const Point& p) const {
            return hash<int>()(p.x) ^ hash<int>()(p.y);
        }
    };
}