#844978 (C++17) No.1975 Zigzag Sequence

• 問題: No.1975 Zigzag Sequence
• ユーザー: 👑 AngrySadEight
• 提出日時: 2023-03-02 11:49:20
• 言語: C++17 (gcc 12.3.0 + boost 1.83.0)
• 結果: AC
• 実行時間: 190 ms / 2,000 ms
• コード長: 4,511 bytes
• コンパイル時間: 6,032 ms
• コンパイル使用メモリ: 313,588 KB
• 実行使用メモリ: 26,564 KB
• 最終ジャッジ日時: 2024-09-17 07:38:56
• 合計ジャッジ時間: 10,814 ms
• ジャッジサーバーID （参考情報）: judge3 / judge4

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	2 ms; 6,812 KB
testcase_01	AC	2 ms; 6,940 KB
testcase_02	AC	2 ms; 6,940 KB
testcase_03	AC	16 ms; 6,940 KB
testcase_04	AC	7 ms; 6,944 KB
testcase_05	AC	135 ms; 18,852 KB
testcase_06	AC	98 ms; 13,564 KB
testcase_07	AC	17 ms; 6,940 KB
testcase_08	AC	81 ms; 12,100 KB
testcase_09	AC	145 ms; 20,572 KB
testcase_10	AC	91 ms; 13,140 KB
testcase_11	AC	102 ms; 17,776 KB
testcase_12	AC	23 ms; 6,944 KB
testcase_13	AC	2 ms; 6,944 KB
testcase_14	AC	2 ms; 6,940 KB
testcase_15	AC	2 ms; 6,944 KB
testcase_16	AC	2 ms; 6,944 KB
testcase_17	AC	2 ms; 6,940 KB
testcase_18	AC	93 ms; 17,840 KB
testcase_19	AC	91 ms; 17,840 KB
testcase_20	AC	112 ms; 18,696 KB
testcase_21	AC	102 ms; 18,712 KB
testcase_22	AC	140 ms; 26,436 KB
testcase_23	AC	146 ms; 26,412 KB
testcase_24	AC	144 ms; 26,432 KB
testcase_25	AC	150 ms; 26,436 KB
testcase_26	AC	145 ms; 18,960 KB
testcase_27	AC	190 ms; 22,448 KB
testcase_28	AC	145 ms; 26,564 KB
testcase_29	AC	138 ms; 26,312 KB
testcase_30	AC	141 ms; 26,436 KB
testcase_31	AC	140 ms; 26,436 KB
testcase_32	AC	92 ms; 17,848 KB
testcase_33	AC	90 ms; 17,848 KB
testcase_34	AC	138 ms; 19,760 KB
testcase_35	AC	138 ms; 19,760 KB

ソースコード

#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")


#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
typedef long long ll;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define repr(i, n) for (int i = (int)(n) - 1; i >= 0; i--)
#define repk(i, k, n) for (int i = k; i < (int)(n); i++)
#define all(v) v.begin(), v.end()
#define mod1 1000000007
#define mod2 998244353
#define mod3 100000007
#define vi vector<int>
#define vs vector<string>
#define vc vector<char>
#define vl vector<ll>
#define vb vector<bool>
#define vvi vector<vector<int>>
#define vvc vector<vector<char>>
#define vvl vector<vector<ll>>
#define vvb vector<vector<bool>>
#define vvvi vector<vector<vector<int>>>
#define vvvl vector<vector<vector<ll>>>
#define pii pair<int,int>
#define pil pair<int,ll>
#define pli pair<ll, int>
#define pll pair<ll, ll>
#define vpii vector<pair<int,int>>
#define vpll vector<pair<ll,ll>>
#define vvpii vector<vector<pair<int,int>>>
#define vvpll vector<vector<pair<ll,ll>>>

template<typename T> void debug(T e){
    cerr << e << endl;
}

template<typename T> void debug(vector<T> &v){
    rep(i, v.size()){
        cerr << v[i] << " ";
    }
    cerr << endl;
}

template<typename T> void debug(vector<vector<T>> &v){
    rep(i, v.size()){
        rep(j, v[i].size()){
            cerr << v[i][j] << " ";
        }
        cerr << endl;
    }
}

template<typename T> void debug(vector<pair<T, T>> &v){
    rep(i,v.size()){
        cerr << v[i].first << " " << v[i].second << endl;
    }
}

template<typename T> void debug(set<T> &st){
    for (auto itr = st.begin(); itr != st.end(); itr++){
        cerr << *itr << " ";
    }
    cerr << endl;
}

template<typename T> void debug(multiset<T> &ms){
    for (auto itr = ms.begin(); itr != ms.end(); itr++){
        cerr << *itr << " ";
    }
    cerr << endl;
}

template<typename T> void debug(map<T, T> &mp){
    for (auto itr = mp.begin(); itr != mp.end(); itr++){
        cerr << itr->first << " " << itr->second << endl;
    }
}

void debug_out(){
    cerr << endl;
}

template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T){
    cerr << H << " ";
    debug_out(T...);
}

ll op(ll a, ll b){
    return a + b;
}

ll e(){
    return 0LL;
}

int main(){
    ll N;
    cin >> N;
    vl A(N);
    rep(i,N) cin >> A[i];

    map<ll, ll> mp;
    for (ll i = 0; i < N; i++){
        mp[A[i]]++;
    }
    vl pow_2(N + 2);
    pow_2[0] = 1;
    for (ll i = 0; i < N + 1; i++){
        pow_2[i + 1] = (pow_2[i] * 2LL) % mod1;
    }
    ll now = 1;
    for (auto itr = mp.begin(); itr != mp.end(); itr++){
        itr->second = now;
        now++;
    }
    vl B(N);
    rep(i,N){
        B[i] = mp[A[i]];
    }
    //debug(B);
    ll ans = 0;
    vvl count(N + 1, vl(0));
    for (ll i = 0; i < N; i++){
        count[B[i]].push_back(i);
    }
    segtree<ll, op, e> seg1(N);
    segtree<ll, op, e> seg2(N);
    // 小さい方のジグザグの寄与を計算
    for (ll i = 1; i <= N; i++){
        for (ll j = 0; j < count[i].size(); j++){
            ll left_val = 0;
            ll right_val = 0;
            if (count[i][j] > 0){
                left_val = seg1.prod(0, count[i][j]);
            }
            if (count[i][j] < N - 1){
                right_val = seg2.prod(count[i][j] + 1, N);
            }
            left_val %= mod1;
            right_val %= mod1;
            ans = (ans + (left_val * right_val) % mod1) % mod1;
        }
        for (ll j = 0; j < count[i].size(); j++){
            seg1.set(count[i][j], pow_2[count[i][j]]);
            seg2.set(count[i][j], pow_2[N - 1 - count[i][j]]);
        }
    }
    segtree<ll, op, e> seg3(N);
    segtree<ll, op, e> seg4(N);
    // 大きい方のジグザグの寄与を計算
    for (ll i = N; i >= 1; i--){
        for (ll j = 0; j < count[i].size(); j++){
            ll left_val = 0;
            ll right_val = 0;
            if (count[i][j] > 0){
                left_val = seg3.prod(0, count[i][j]);
            }
            if (count[i][j] < N - 1){
                right_val = seg4.prod(count[i][j] + 1, N);
            }
            left_val %= mod1;
            right_val %= mod1;
            ans = (ans + (left_val * right_val) % mod1) % mod1;
        }
        for (ll j = 0; j < count[i].size(); j++){
            seg3.set(count[i][j], pow_2[count[i][j]]);
            seg4.set(count[i][j], pow_2[N - 1 - count[i][j]]);
        }
    }
    cout << ans << endl;
}