結果

問題 No.843 Triple Primes
ユーザー iiljjiiljj
提出日時 2020-09-07 23:18:55
言語 C++17
(gcc 12.3.0 + boost 1.83.0)
結果
AC  
実行時間 14 ms / 2,000 ms
コード長 6,455 bytes
コンパイル時間 2,001 ms
コンパイル使用メモリ 210,384 KB
実行使用メモリ 5,668 KB
最終ジャッジ日時 2024-05-07 00:19:52
合計ジャッジ時間 3,603 ms
ジャッジサーバーID
（参考情報） 		judge4 / judge1
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テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 1 ms
5,248 KB
testcase_01 AC 14 ms
5,404 KB
testcase_02 AC 2 ms
5,376 KB
testcase_03 AC 2 ms
5,376 KB
testcase_04 AC 2 ms
5,376 KB
testcase_05 AC 2 ms
5,376 KB
testcase_06 AC 2 ms
5,376 KB
testcase_07 AC 11 ms
5,376 KB
testcase_08 AC 12 ms
5,376 KB
testcase_09 AC 14 ms
5,536 KB
testcase_10 AC 11 ms
5,376 KB
testcase_11 AC 12 ms
5,376 KB
testcase_12 AC 13 ms
5,400 KB
testcase_13 AC 13 ms
5,404 KB
testcase_14 AC 12 ms
5,376 KB
testcase_15 AC 11 ms
5,376 KB
testcase_16 AC 11 ms
5,376 KB
testcase_17 AC 2 ms
5,376 KB
testcase_18 AC 2 ms
5,376 KB
testcase_19 AC 2 ms
5,376 KB
testcase_20 AC 5 ms
5,376 KB
testcase_21 AC 3 ms
5,376 KB
testcase_22 AC 8 ms
5,376 KB
testcase_23 AC 8 ms
5,376 KB
testcase_24 AC 5 ms
5,376 KB
testcase_25 AC 4 ms
5,376 KB
testcase_26 AC 13 ms
5,536 KB
testcase_27 AC 3 ms
5,376 KB
testcase_28 AC 12 ms
5,408 KB
testcase_29 AC 5 ms
5,376 KB
testcase_30 AC 14 ms
5,408 KB
testcase_31 AC 3 ms
5,376 KB
testcase_32 AC 2 ms
5,376 KB
testcase_33 AC 6 ms
5,376 KB
testcase_34 AC 8 ms
5,376 KB
testcase_35 AC 14 ms
5,668 KB
testcase_36 AC 4 ms
5,376 KB
testcase_37 AC 11 ms
5,376 KB
testcase_38 AC 8 ms
5,376 KB
testcase_39 AC 13 ms
5,404 KB
testcase_40 AC 1 ms
5,376 KB
testcase_41 AC 1 ms
5,376 KB
testcase_42 AC 12 ms
5,376 KB
testcase_43 AC 13 ms
5,400 KB
権限があれば一括ダウンロードができます

ソースコード

diff # 

/* #region Head */

// #define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;

using ll = long long;
using ull = unsigned long long;
using ld = long double;
using pll = pair<ll, ll>;
template <class T> using vc = vector<T>;
template <class T> using vvc = vc<vc<T>>;
using vll = vc<ll>;
using vvll = vvc<ll>;
using vld = vc<ld>;
using vvld = vvc<ld>;
using vs = vc<string>;
using vvs = vvc<string>;
template <class T, class U> using um = unordered_map<T, U>;
template <class T> using pq = priority_queue<T>;
template <class T> using pqa = priority_queue<T, vc<T>, greater<T>>;
template <class T> using us = unordered_set<T>;

#define REP(i, m, n) for (ll i = (m), i##_len = (ll)(n); i < i##_len; ++(i))
#define REPM(i, m, n) for (ll i = (m), i##_max = (ll)(n); i <= i##_max; ++(i))
#define REPR(i, m, n) for (ll i = (m), i##_min = (ll)(n); i >= i##_min; --(i))
#define REPD(i, m, n, d) for (ll i = (m), i##_len = (ll)(n); i < i##_len; i += (d))
#define REPMD(i, m, n, d) for (ll i = (m), i##_max = (ll)(n); i <= i##_max; i += (d))
#define REPI(itr, ds) for (auto itr = ds.begin(); itr != ds.end(); itr++)
#define ALL(x) begin(x), end(x)
#define SIZE(x) ((ll)(x).size())
#define PERM(c)                                                                                                        \
    sort(ALL(c));                                                                                                      \
    for (bool c##p = 1; c##p; c##p = next_permutation(ALL(c)))
#define UNIQ(v) v.erase(unique(ALL(v)), v.end());

#define endl '\n'
#define sqrt sqrtl
#define floor floorl
#define log2 log2l

constexpr ll INF = 1'010'000'000'000'000'017LL;
constexpr int IINF = 1'000'000'007LL;
constexpr ll MOD = 1'000'000'007LL; // 1e9 + 7
constexpr ld EPS = 1e-12;
constexpr ld PI = 3.14159265358979323846;

template <typename T> istream &operator>>(istream &is, vc<T> &vec) { // vector 入力
    for (T &x : vec) is >> x;
    return is;
}
template <typename T> ostream &operator<<(ostream &os, vc<T> &vec) { // vector 出力 (for dump)
    os << "{";
    REP(i, 0, SIZE(vec)) os << vec[i] << (i == i_len - 1 ? "" : ", ");
    os << "}";
    return os;
}
template <typename T> ostream &operator>>(ostream &os, vc<T> &vec) { // vector 出力 (inline)
    REP(i, 0, SIZE(vec)) os << vec[i] << (i == i_len - 1 ? "\n" : " ");
    return os;
}

template <typename T, typename U> istream &operator>>(istream &is, pair<T, U> &pair_var) { // pair 入力
    is >> pair_var.first >> pair_var.second;
    return is;
}
template <typename T, typename U> ostream &operator<<(ostream &os, pair<T, U> &pair_var) { // pair 出力
    os << "(" << pair_var.first << ", " << pair_var.second << ")";
    return os;
}

// map, um, set, us 出力
template <class T> ostream &out_iter(ostream &os, T &map_var) {
    os << "{";
    REPI(itr, map_var) {
        os << *itr;
        auto itrcp = itr;
        if (++itrcp != map_var.end()) os << ", ";
    }
    return os << "}";
}
template <typename T, typename U> ostream &operator<<(ostream &os, map<T, U> &map_var) { return out_iter(os, map_var); }
template <typename T, typename U> ostream &operator<<(ostream &os, um<T, U> &map_var) {
    os << "{";
    REPI(itr, map_var) {
        auto [key, value] = *itr;
        os << "(" << key << ", " << value << ")";
        auto itrcp = itr;
        if (++itrcp != map_var.end()) os << ", ";
    }
    os << "}";
    return os;
}
template <typename T> ostream &operator<<(ostream &os, set<T> &set_var) { return out_iter(os, set_var); }
template <typename T> ostream &operator<<(ostream &os, us<T> &set_var) { return out_iter(os, set_var); }
template <typename T> ostream &operator<<(ostream &os, pq<T> &pq_var) {
    pq<T> pq_cp(pq_var);
    os << "{";
    if (!pq_cp.empty()) {
        os << pq_cp.top(), pq_cp.pop();
        while (!pq_cp.empty()) os << ", " << pq_cp.top(), pq_cp.pop();
    }
    return os << "}";
}

// dump
#define DUMPOUT cerr
void dump_func() { DUMPOUT << endl; }
template <class Head, class... Tail> void dump_func(Head &&head, Tail &&... tail) {
    DUMPOUT << head;
    if (sizeof...(Tail) > 0) DUMPOUT << ", ";
    dump_func(move(tail)...);
}

// chmax (更新「される」かもしれない値が前)
template <typename T, typename U, typename Comp = less<>> bool chmax(T &xmax, const U &x, Comp comp = {}) {
    if (comp(xmax, x)) {
        xmax = x;
        return true;
    }
    return false;
}

// chmin (更新「される」かもしれない値が前)
template <typename T, typename U, typename Comp = less<>> bool chmin(T &xmin, const U &x, Comp comp = {}) {
    if (comp(x, xmin)) {
        xmin = x;
        return true;
    }
    return false;
}

// ローカル用
#define DEBUG_

#ifdef DEBUG_
#define DEB
#define dump(...)                                                                                                      \
    DUMPOUT << "  " << string(#__VA_ARGS__) << ": "                                                                    \
            << "[" << to_string(__LINE__) << ":" << __FUNCTION__ << "]" << endl                                        \
            << "    ",                                                                                                 \
        dump_func(__VA_ARGS__)
#else
#define DEB if (false)
#define dump(...)
#endif

struct AtCoderInitialize {
    static constexpr int IOS_PREC = 15;
    static constexpr bool AUTOFLUSH = false;
    AtCoderInitialize() {
        ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
        cout << fixed << setprecision(IOS_PREC);
        if (AUTOFLUSH) cout << unitbuf;
    }
} ATCODER_INITIALIZE;

void Yn(bool p) { cout << (p ? "Yes" : "No") << endl; }
void YN(bool p) { cout << (p ? "YES" : "NO") << endl; }

/* #endregion */

vll getprimes(ll n) {
    vc<bool> sieve(n + 1, false);
    ll sqrtn = sqrtl(n);
    REPM(i, 2, sqrtn) {
        if (sieve[i]) continue;
        REPMD(j, i * i, n, i) sieve[j] = true;
    }
    vll ret;
    REPM(i, 2, n) if (!sieve[i]) ret.push_back(i);
    return ret;
}

// Problem
void solve() {
    ll n;
    cin >> n;

    vll primes = getprimes(n);
    // dump(SIZE(primes)); // 41538 when n=500000

    set<ll> r2s;
    for (ll r : primes) r2s.insert(r * r);

    ll ret = 0;
    for (ll q : primes) {
        ll needle = 2 + q;
        if (r2s.count(needle)) ret += (q == 2) ? 1 : 2;
    }
    cout << ret << endl;
}

// entry point
int main() {
    solve();
    return 0;
}
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