#pragma once

#include <cstdint>
#include <string>
#include <vector>

std::uint64_t hash(std::string const& s);

class Hash_Table
{
public:

    Hash_Table();

    void insert(std::string const& key, int value);
    void remove(std::string const& key);
    int& lookup(std::string const& key);
    bool contains(std::string const& key) const;

    std::vector<std::string> keys() const;

private:

    unsigned find(std::string const& key) const;
    void resize(unsigned new_size);

private:

    struct Entry
    {
        std::string key   { };
        int         value { };
        bool        valid { };
    };

    std::vector<Entry> table;
};