ds/hashmap.hpp

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• Last update: 2024-01-28 16:26:28+09:00
• Include: #include "ds/hashmap.hpp"

Required by

• ds/static_range_frequency.hpp
• ds/to_small_key.hpp
• geo/closest_pair.hpp
• geo/range_closest_pair_query.hpp
• graph/eulerwalk.hpp
• graph/vs_to_es.hpp
• mod/mod_kth_root.hpp
• mod/mod_log.hpp
• nt/array_on_divisors.hpp
• nt/discrete_log.hpp
• other/connected_dp.hpp

Verified with

• test/aoj/CGL_5_A.test.cpp
• test/library_checker/datastructure/associative_array_hashmap.test.cpp
• test/library_checker/datastructure/set_xor_min.test.cpp
• test/library_checker/datastructure/static_range_freq.test.cpp
• test/library_checker/datastructure/static_range_frequency.test.cpp
• test/library_checker/datastructure/static_range_mode_query.test.cpp
• test/library_checker/graph/eulerwalk_d.test.cpp
• test/library_checker/graph/eulerwalk_ud.test.cpp
• test/library_checker/math/discrete_logarithm_mod.test.cpp
• test/library_checker/math/kth_root_mod.test.cpp
• test/mytest/range_closest_pair.test.cpp
• test/mytest/tdpc_grid_dp.test.cpp
• test/yukicoder/1339.test.cpp
• test/yukicoder/1383.test.cpp
• test/yukicoder/1397.test.cpp
• test/yukicoder/1561.test.cpp
• test/yukicoder/1634.test.cpp
• test/yukicoder/1726.test.cpp
• test/yukicoder/1728.test.cpp
• test/yukicoder/1769.test.cpp
• test/yukicoder/1881.test.cpp
• test/yukicoder/2102.test.cpp
• test/yukicoder/2167.test.cpp
• test/yukicoder/2264.test.cpp
• test/yukicoder/2578.test.cpp
• test/yukicoder/263.test.cpp
• test/yukicoder/541.test.cpp
• test/yukicoder/578.test.cpp
• test/yukicoder/579.test.cpp
• test_atcoder/abc212g.test.cpp
• test_atcoder/abc220g.test.cpp
• test_atcoder/abc222g.test.cpp
• test_atcoder/abc227g.test.cpp
• test_atcoder/abc270_g.test.cpp
• test_atcoder/abc273_e.test.cpp
• test_atcoder/abc335g.test.cpp
• test_atcoder/abc339f.test.cpp
• test_atcoder/arc157a.test.cpp

Code

#pragma once

// u64 -> Val

template <typename Val>
struct HashMap {
  HashMap(u32 n = 0) { build(n); }
  void build(u32 n) {
    u32 k = 8;
    while (k < n * 2) k *= 2;
    cap = k / 2, mask = k - 1;
    key.resize(k), val.resize(k), used.assign(k, 0);
  }
  void clear() { build(0); }
  int size() { return len(used) - cap; }

  int index(const u64& k) {
    int i = 0;
    for (i = hash(k); used[i] && key[i] != k; i = (i + 1) & mask) {}
    return i;
  }

  Val& operator[](const u64& k) {
    if (cap == 0) extend();
    int i = index(k);
    if (!used[i]) { used[i] = 1, key[i] = k, val[i] = Val{}, --cap; }
    return val[i];
  }

  Val get(const u64& k, Val default_value) {
    int i = index(k);
    return (used[i] ? val[i] : default_value);
  }

  bool count(const u64& k) {
    int i = index(k);
    return used[i] && key[i] == k;
  }

  // f(key, val)

  template <typename F>
  void enumerate_all(F f) {
    FOR(i, len(used)) if (used[i]) f(key[i], val[i]);
  }

private:
  u32 cap, mask;
  vc<u64> key;
  vc<Val> val;
  vc<bool> used;

  u64 hash(u64 x) {
    static const u64 FIXED_RANDOM
        = std::chrono::steady_clock::now().time_since_epoch().count();
    x += FIXED_RANDOM;
    x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
    x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
    return (x ^ (x >> 31)) & mask;
  }

  void extend() {
    vc<pair<u64, Val>> dat;
    dat.reserve(len(used) - cap);
    FOR(i, len(used)) {
      if (used[i]) dat.eb(key[i], val[i]);
    }
    build(2 * len(dat));
    for (auto& [a, b]: dat) (*this)[a] = b;
  }
};

#line 2 "ds/hashmap.hpp"

// u64 -> Val

template <typename Val>
struct HashMap {
  HashMap(u32 n = 0) { build(n); }
  void build(u32 n) {
    u32 k = 8;
    while (k < n * 2) k *= 2;
    cap = k / 2, mask = k - 1;
    key.resize(k), val.resize(k), used.assign(k, 0);
  }
  void clear() { build(0); }
  int size() { return len(used) - cap; }

  int index(const u64& k) {
    int i = 0;
    for (i = hash(k); used[i] && key[i] != k; i = (i + 1) & mask) {}
    return i;
  }

  Val& operator[](const u64& k) {
    if (cap == 0) extend();
    int i = index(k);
    if (!used[i]) { used[i] = 1, key[i] = k, val[i] = Val{}, --cap; }
    return val[i];
  }

  Val get(const u64& k, Val default_value) {
    int i = index(k);
    return (used[i] ? val[i] : default_value);
  }

  bool count(const u64& k) {
    int i = index(k);
    return used[i] && key[i] == k;
  }

  // f(key, val)

  template <typename F>
  void enumerate_all(F f) {
    FOR(i, len(used)) if (used[i]) f(key[i], val[i]);
  }

private:
  u32 cap, mask;
  vc<u64> key;
  vc<Val> val;
  vc<bool> used;

  u64 hash(u64 x) {
    static const u64 FIXED_RANDOM
        = std::chrono::steady_clock::now().time_since_epoch().count();
    x += FIXED_RANDOM;
    x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
    x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
    return (x ^ (x >> 31)) & mask;
  }

  void extend() {
    vc<pair<u64, Val>> dat;
    dat.reserve(len(used) - cap);
    FOR(i, len(used)) {
      if (used[i]) dat.eb(key[i], val[i]);
    }
    build(2 * len(dat));
    for (auto& [a, b]: dat) (*this)[a] = b;
  }
};

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