Hash Table, Clear Easily (C++ 11)

HashTable.hpp

// Copyright [2018] <Copyright SF-Zhou>
// Author: SF-Zhou
// Email: [email protected]

#ifndef HASHTABLE_HPP_
#define HASHTABLE_HPP_

#include <cstring>

namespace Utils {

template <class Dtype, int Size>
class HashTable {
  Dtype n[Size];
  uint64_t s[Size];
  int h[Size];
  int v[Size];
  int siz, id;

 public:
  HashTable() {
    clear();
  }

  void clear() {
    ++id;
    siz = 0;
  }

  void deep_clear() {
    memset(v, 0, sizeof(v));
    id = 1;
    siz = 0;
  }

  int size() const {
    return siz;
  }

  void set(uint64_t status, Dtype value) {
    int hs = status % Size;

    while (v[hs] == id && s[h[hs]] != status)
      if (++hs == Size) hs = 0;

    if (v[hs] != id) {
      s[siz] = status;
      n[siz] = value;
      v[hs] = id;
      h[hs] = siz;
      ++siz;
    } else {
      n[h[hs]] = value;
    }
  }

  // NOLINTNEXTLINE(runtime/references)
  bool get(uint64_t status, Dtype &value) {
    int hs = status % Size;

    while (v[hs] == id && s[h[hs]] != status)
      if (++hs == Size) hs = 0;

    if (v[hs] == id) {
      value = n[h[hs]];
      return true;
    } else {
      return false;
    }
  }
};

}  // namespace Utils

#endif  // HASHTABLE_HPP_