結果

問題 No.1079 まお
コンテスト
ユーザー minato
提出日時 2020-10-18 05:40:59
言語 C++17(gcc12)
(gcc 12.3.0 + boost 1.87.0)
結果
WA  
実行時間 -
コード長 7,926 bytes
コンパイル時間 12,448 ms
コンパイル使用メモリ 296,196 KB
最終ジャッジ日時 2025-01-15 11:28:10
ジャッジサーバーID
（参考情報） 		judge5 / judge1
このコードへのチャレンジ
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ファイルパターン 結果
sample AC * 2
other AC * 17 WA * 13
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 # 

#ifdef ONLINE_JUDGE
#pragma GCC target("avx2,avx")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#endif
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ull = unsigned long long;
using i128 = __int128_t;
using pii = pair<int, int>;
using pll = pair<long long, long long>;
#define rep(i, n) for (int i = 0; i < (n); i++)
#define all(x) (x).begin(), (x).end()
constexpr char ln = '\n';
istream& operator>>(istream& is, __int128_t& x) {
    x = 0;
    string s;
    is >> s;
    int n = int(s.size()), it = 0;
    if (s[0] == '-') it++;
    for (; it < n; it++) x = (x * 10 + s[it] - '0');
    if (s[0] == '-') x = -x;
    return is;
}
ostream& operator<<(ostream& os, __int128_t x) {
    if (x == 0) return os << 0;
    if (x < 0) os << '-', x = -x;
    deque<int> deq;
    while (x) deq.emplace_front(x % 10), x /= 10;
    for (int e : deq) os << e;
    return os;
}
template<class T1, class T2>
ostream& operator<<(ostream& os, const pair<T1, T2>& p) {
    return os << "(" << p.first << ", " << p.second << ")";
}
template<class T> 
ostream& operator<<(ostream& os, const vector<T>& v) {
    os << "{";
    for (int i = 0; i < int(v.size()); i++) {
        if (i) os << ", ";
        os << v[i];
    }
    return os << "}";
}
template<class Container> inline int SZ(Container& v) { return int(v.size()); }
template<typename T> inline void UNIQUE(vector<T>& v) { v.erase(unique(v.begin(), v.end()), v.end()); }
template<class T1, class T2> inline bool chmax(T1& a, T2 b) { if (a < b) {a = b; return true ;} return false ;}
template<class T1, class T2> inline bool chmin(T1& a, T2 b) { if (a > b) {a = b; return true ;} return false ;}
inline int topbit(int x) { return x == 0 ? -1 : 31 - __builtin_clz(x); }
inline int topbit(long long x) { return x == 0 ? -1 : 63 - __builtin_clzll(x); }
inline int botbit(int x) { return x == 0 ? 32 : __builtin_ctz(x); }
inline int botbit(long long x) { return x == 0 ? 64 : __builtin_ctzll(x); }
inline int popcount(int x) { return __builtin_popcount(x); }
inline int popcount(long long x) { return __builtin_popcountll(x); }
inline int kthbit(long long x, int k) { return (x>>k) & 1; }
inline constexpr long long TEN(int x) { return x == 0 ? 1 : TEN(x-1) * 10; }
namespace detail {
    template<typename Tp, int Nb>
    auto make_vector(vector<int>& sizes, Tp const& x) {
        if constexpr (Nb == 1) {
            return vector(sizes[0], x);
        } else {
            int size = sizes[Nb-1];
            sizes.pop_back();
            return vector(size, make_vector<Tp, Nb-1>(sizes, x));
        }
    }
}
template<typename Tp, int Nb>
auto make_vector(int const(&sizes)[Nb], Tp const& x = Tp()) {
    vector<int> s(Nb);
    for (int i = 0; i < Nb; i++) s[i] = sizes[Nb-i-1];
    return detail::make_vector<Tp, Nb>(s, x);
}
inline void print() { cout << "\n"; }
template<class T>
inline void print(const vector<T>& v) {
    for (int i = 0; i < int(v.size()); i++) {
        if (i) cout << " ";
        cout << v[i];
    }
    print();
}
template<class T, class... Args>
inline void print(const T& x, const Args& ... args) {
    cout << x << " ";
    print(args...);
}
#ifdef MINATO_LOCAL
inline void debug_out() { cerr << endl; }
template <class T, class... Args>
inline void debug_out(const T& x, const Args& ... args) {
    cerr << " " << x;
    debug_out(args...);
}
#define debug(...) cerr << __LINE__ << " : [" << #__VA_ARGS__ << "] =", debug_out(__VA_ARGS__)
#define dump(x) cerr << __LINE__ << " : " << #x << " = " << (x) << endl
#else
#define debug(...) (void(0))
#define dump(x) (void(0))
#endif
struct fast_ios { fast_ios() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(20); }; } fast_ios_;
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

template<class T, class F>
struct SegmentTree {
  private:
    F op;
    T e;
    int _n, size ,log;
    vector<T> node;

  public:
    SegmentTree() {}
    SegmentTree(const F& op, T e, int n) : SegmentTree(op, e, vector<T>(n, e)) {}
    SegmentTree(const F& op, T e, const vector<T>& v) : op(op), e(e), _n(int(v.size())), log(0) {
        while ((1<<log) < _n) log++;
        size = 1 << log;
        node = vector<T> (2 * size, e);
        for (int i = 0; i < _n; i++) node[size + i] = v[i];
        for (int i = size - 1; i >= 1; i--) {
            update(i);
        }
    }

    // (0-indexed)
    void set(int p, T x) {
        assert(0 <= p && p < _n);
        p += size;
        node[p] = x;
        for (int i = 1; i <= log; i++) update(p >> i);
    }

    // [l, r) (0-indexed)
    T get(int l, int r) {
        if (l >= r) return e;
        T resl = e, resr = e;
        l += size; r += size;
        while (l < r) {
            if (l & 1) resl = op(resl, node[l++]);
            l >>= 1;
            if (r & 1) resr = op(node[--r], resr);
            r >>= 1;
        }
        return op(resl, resr);
    }

    T all_get() { return node[1]; }

    template<class C> 
    int max_right(int l, const C& check) {
        assert(0 <= l && l <= _n);
        assert(check(e));
        if (l == _n) return _n;
        l += size;
        T sm = e;
        do {
            while (~l & 1) l >>= 1;
            if (!check(op(sm, node[l]))) {
                while (l < size) {
                    l = (2 * l);
                    if (check(op(sm, node[l]))) {
                        sm = op(sm, node[l]);
                        l++;
                    }
                }
                return l - size;
            }
            sm = op(sm, node[l]);
            l++;
        } while ((l & -l) != l);
        return _n;
    }

    template<class C> 
    int min_left(int r, const C& check) {
        assert(0 <= r && r <= _n);
        assert(check(e));
        if (r == 0) return 0;
        r += size;
        T sm = e;
        do {
            r--;
            while (r > 1 && (r & 1)) r >>= 1;
            if (!check(op(node[r], sm))) {
                while (r < size) {
                    r = (2 * r + 1);
                    if (f(op(node[r], sm))) {
                        sm = op(node[r], sm);
                        r--;
                    }
                }
                return r + 1 - size;
            }
            sm = op(node[r], sm);
        } while ((r & -r) != r);
        return 0;
    }

    T operator[](int p) {
        assert(0 <= p && p < _n);
        return node[p + size];
    }

  private:

    void update(int k) { node[k] = op(node[2 * k], node[2 * k + 1]); }
};

constexpr int INF = TEN(9)+1;

int main() {
    int N,K; cin >> N >> K;
    vector<int> A(N);
    rep(i,N) cin >> A[i];

    auto f=[](pii a, pii b) {
        if (a.first < b.first) {
            return a;
        }
        if (a.first > b.first) {
            return b;
        }
        return pii(a.first,a.second+b.second);
    };
    constexpr pii e = pii(INF,0);
    vector<pii> A_(N);
    rep(i,N) A_[i] = pii(A[i],1);
    SegmentTree seg(f,e,A_);

    ll ans = 0;
    auto check=[](pii a) { return a.second <= 1; };
    auto dfs=[&](auto self, int l, int r)->void {
        if (r-l==1) {
            if (A[l]*2==K) ans++;
            return;
        }

        int m = (r+l)/2;
        self(self,l,m);
        self(self,m,r);
        int cur_r = m;
        map<int, pll> dic;
        for (int pos = l; pos < m; pos++) {
            int okr = seg.max_right(pos,check);
            while (cur_r < min(okr,r)) {
                auto[len,cnt] = dic[A[cur_r]];
                len += cur_r - m + 1;
                cnt++;
                dic[A[cur_r]] = pll(len,cnt);
                cur_r++;
            }
            if (dic.count(K-A[pos])) {
                auto[len,cnt] = dic[K-A[pos]];
                ll val = len + cnt*(m-pos);
                ans += val;
            }
        }
        return;
    };
    dfs(dfs,0,N);
    cout << ans << ln;
}
0