結果
問題 | No.1975 Zigzag Sequence |
ユーザー |
👑 ![]() |
提出日時 | 2023-03-02 11:45:01 |
言語 | C++17(gcc12) (gcc 12.3.0 + boost 1.87.0) |
結果 |
WA
|
実行時間 | - |
コード長 | 4,389 bytes |
コンパイル時間 | 25,706 ms |
コンパイル使用メモリ | 358,404 KB |
最終ジャッジ日時 | 2025-02-11 01:01:40 |
ジャッジサーバーID (参考情報) |
judge2 / judge5 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 9 WA * 24 |
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);}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);}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;}