#769630 (C++17) No.1975 Zigzag Sequence

• 問題: No.1975 Zigzag Sequence
• ユーザー: milanis48663220
• 提出日時: 2022-06-10 21:58:16
• 言語: C++17 (gcc 12.3.0 + boost 1.83.0)
• 結果: AC
• 実行時間: 160 ms / 2,000 ms
• コード長: 5,129 bytes
• コンパイル時間: 1,253 ms
• コンパイル使用メモリ: 130,788 KB
• 実行使用メモリ: 9,964 KB
• 最終ジャッジ日時: 2023-10-21 05:08:40
• 合計ジャッジ時間: 5,349 ms
• ジャッジサーバーID （参考情報）: judge13 / judge12

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	2 ms; 4,348 KB
testcase_01	AC	2 ms; 4,348 KB
testcase_02	AC	2 ms; 4,348 KB
testcase_03	AC	15 ms; 4,348 KB
testcase_04	AC	7 ms; 4,348 KB
testcase_05	AC	116 ms; 6,720 KB
testcase_06	AC	88 ms; 6,688 KB
testcase_07	AC	17 ms; 4,348 KB
testcase_08	AC	70 ms; 5,224 KB
testcase_09	AC	128 ms; 8,140 KB
testcase_10	AC	90 ms; 6,160 KB
testcase_11	AC	94 ms; 6,384 KB
testcase_12	AC	22 ms; 4,348 KB
testcase_13	AC	1 ms; 4,348 KB
testcase_14	AC	2 ms; 4,348 KB
testcase_15	AC	2 ms; 4,348 KB
testcase_16	AC	2 ms; 4,348 KB
testcase_17	AC	2 ms; 4,348 KB
testcase_18	AC	55 ms; 5,676 KB
testcase_19	AC	56 ms; 5,676 KB
testcase_20	AC	88 ms; 6,644 KB
testcase_21	AC	88 ms; 6,520 KB
testcase_22	AC	143 ms; 9,964 KB
testcase_23	AC	141 ms; 9,964 KB
testcase_24	AC	150 ms; 9,964 KB
testcase_25	AC	145 ms; 9,964 KB
testcase_26	AC	119 ms; 6,560 KB
testcase_27	AC	160 ms; 9,076 KB
testcase_28	AC	139 ms; 9,964 KB
testcase_29	AC	137 ms; 9,964 KB
testcase_30	AC	144 ms; 9,964 KB
testcase_31	AC	151 ms; 9,964 KB
testcase_32	AC	55 ms; 5,676 KB
testcase_33	AC	55 ms; 5,676 KB
testcase_34	AC	123 ms; 7,084 KB
testcase_35	AC	131 ms; 7,084 KB

ソースコード

#include <iostream>
#include <algorithm>
#include <iomanip>
#include <vector>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <tuple>
#include <cmath>
#include <numeric>
#include <functional>
#include <cassert>

#define debug_value(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << #x << "=" << x << endl;
#define debug(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << x << endl;

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }

using namespace std;
typedef long long ll;

template<typename T>
vector<vector<T>> vec2d(int n, int m, T v){
    return vector<vector<T>>(n, vector<T>(m, v));
}

template<typename T>
vector<vector<vector<T>>> vec3d(int n, int m, int k, T v){
    return vector<vector<vector<T>>>(n, vector<vector<T>>(m, vector<T>(k, v)));
}

template<typename T>
void print_vector(vector<T> v, char delimiter=' '){
    if(v.empty()) {
        cout << endl;
        return;
    }
    for(int i = 0; i+1 < v.size(); i++) cout << v[i] << delimiter;
    cout << v.back() << endl;
}

const ll MOD = 1000000007;

class ModInt{
    public:
    ll v;
    ModInt(ll _v = 0){
        if(_v < 0) _v = (_v%MOD)+MOD;
        if(_v >= MOD) _v %= MOD;
        v = _v;
    }
    ModInt operator+(ll n){
        return ModInt((v+n)%MOD);
    }
    ModInt operator-(ll n){
        return ModInt((v-n+MOD)%MOD);
    }
    ModInt operator*(ll n){
        if(n >= MOD) n %= MOD;
        return ModInt((v*n)%MOD);
    }
    ModInt operator/(ll n){
        return ModInt((ModInt(n).inv()*v).v%MOD);
    }

    ModInt &operator+=(ll n){
        v = (v+n)%MOD;
        return *this;
    }
    ModInt &operator-=(ll n){
        v = (v-n+MOD)%MOD;
        return *this;
    }
    ModInt &operator*=(ll n){
        v = (v*n+MOD)%MOD;
        return *this;
    }
    
    
    ModInt operator+(ModInt n){
        return ModInt((v+n.v)%MOD);
    }
    ModInt operator-(ModInt n){
        return ModInt((v-n.v+MOD)%MOD);
    }
    ModInt operator*(ModInt n){
        return ModInt((v*n.v)%MOD);
    }
    ModInt operator/(ModInt n){
        return ModInt((n.inv()*v).v%MOD);
    }

    ModInt &operator+=(ModInt n){
        v = (v+n.v)%MOD;
        return *this;
    }
    ModInt &operator-=(ModInt n){
        v = (v-n.v+MOD)%MOD;
        return *this;
    }
    ModInt &operator*=(ModInt n){
        v = (v*n.v)%MOD;
        return *this;
    }

    bool operator==(ModInt n){
        return v == n.v;
    }
    bool operator!=(ModInt n){
        return v != n.v;
    }
    ModInt &operator=(ll n){
        v = n%MOD;
        return *this;
    }

    ModInt inv(){
        if(v == 1) return ModInt(1);
        else return ModInt(MOD-ModInt(MOD%v).inv().v*(MOD/v)%MOD);
    }
};

ostream& operator<<(ostream& os, const ModInt& m){
    os << m.v;
    return os;
}

istream & operator >> (istream &in,  ModInt &m){
    in >> m.v;
    return in;
}

ModInt pow(ModInt a, ll n) {
    assert(n >= 0);
	ModInt ans = 1;
    while (n > 0) {
        if (n&1) ans = ans*a;
        a = a*a;
        n >>= 1;
    }
	return ans;
}


template<typename T>
class Compress{
    public:
    vector<T> data;
    int offset;
    Compress(vector<T> data_, int offset=0): offset(offset){
        set<T> st;
        for(T x: data_) st.insert(x);
        for(T x: st) data.push_back(x);
    };
    int operator[](T x) {
        auto p = lower_bound(data.begin(), data.end(), x);
        assert(x == *p);
        return offset+(p-data.begin());
	}
    T inv(int x){
        return data[x-offset];
    }
    int size(){
        return data.size();
    }
};

//1-indexed
template <typename T>
struct bit{
    int n;
    vector<T> data;

    bit(int n_){
        n = 1;
        while(n < n_) n *= 2;
        data = vector<T>(n+1);
        for(int i = 0; i <= n; i++) data[i] = 0;
    }
    
    T sum(int i){
        T ret = 0;
        while(i > 0){
            ret += data[i];
            i -= i&-i;
        }
        return ret;
    }

    void add(int i, T x){
        while(i <= n){
            data[i] += x;
            i += i&-i;
        }
    }
};

using mint = ModInt;

mint count(vector<int> a){
    auto cp = Compress<int>(a, 1);
    int n = a.size(), m = cp.size();
    bit<mint> bt_left(m);
    vector<mint> cnt_left(n), cnt_right(n);
    for(int i = 0; i < n; i++){
        int idx = cp[a[i]];
        bt_left.add(idx, pow(mint(2), i));
        cnt_left[i] = bt_left.sum(idx-1);
    }
    bit<mint> bt_right(m);
    for(int i = n-1; i >= 0; i--){
        int idx = cp[a[i]];
        bt_right.add(idx, pow(mint(2), n-1-i));
        cnt_right[i] = bt_right.sum(idx-1);
    }
    mint ans = 0;
    for(int i = 0; i < n; i++) ans += cnt_left[i]*cnt_right[i];
    return ans;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout << setprecision(10) << fixed;
    int n; cin >> n;
    vector<int> a(n);
    for(int i = 0; i < n; i++) cin >> a[i];
    mint ans = count(a);
    for(int i = 0; i < n; i++) a[i] *= -1;
    ans += count(a);
    cout << ans << endl;
}