結果
問題 | No.2250 Split Permutation |
ユーザー |
|
提出日時 | 2023-03-17 22:30:44 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 316 ms / 3,000 ms |
コード長 | 5,221 bytes |
コンパイル時間 | 2,065 ms |
コンパイル使用メモリ | 204,592 KB |
最終ジャッジ日時 | 2025-02-11 13:35:56 |
ジャッジサーバーID (参考情報) |
judge4 / judge1 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 35 |
ソースコード
#include<bits/stdc++.h>using namespace std;//#pragma GCC optimize("Ofast")#define rep(i,n) for(ll i=0;i<n;i++)#define repl(i,l,r) for(ll i=(l);i<(r);i++)#define per(i,n) for(ll i=(n)-1;i>=0;i--)#define perl(i,r,l) for(ll i=r-1;i>=l;i--)#define fi first#define se second#define pb push_back#define ins insert#define pqueue(x) priority_queue<x,vector<x>,greater<x>>#define all(x) (x).begin(),(x).end()#define CST(x) cout<<fixed<<setprecision(x)#define vtpl(x,y,z) vector<tuple<x,y,z>>#define rev(x) reverse(x);using ll=long long;using vl=vector<ll>;using vvl=vector<vector<ll>>;using pl=pair<ll,ll>;using vpl=vector<pl>;using vvpl=vector<vpl>;const ll MOD=1000000007;const ll MOD9=998244353;const int inf=1e9+10;const ll INF=4e18;const ll dy[9]={0,1,-1,0,1,1,-1,-1,0};const ll dx[9]={1,0,0,-1,1,-1,1,-1,0};template<class T> inline bool chmin(T& a, T b) {if (a > b) {a = b;return true;}return false;}template<class T> inline bool chmax(T& a, T b) {if (a < b) {a = b;return true;}return false;}const int mod = MOD9;const int max_n = 200005;struct mint {ll x; // typedef long long ll;mint(ll x=0):x((x%mod+mod)%mod){}mint operator-() const { return mint(-x);}mint& operator+=(const mint a) {if ((x += a.x) >= mod) x -= mod;return *this;}mint& operator-=(const mint a) {if ((x += mod-a.x) >= mod) x -= mod;return *this;}mint& operator*=(const mint a) { (x *= a.x) %= mod; return *this;}mint operator+(const mint a) const { return mint(*this) += a;}mint operator-(const mint a) const { return mint(*this) -= a;}mint operator*(const mint a) const { return mint(*this) *= a;}mint pow(ll t) const {if (!t) return 1;mint a = pow(t>>1);a *= a;if (t&1) a *= *this;return a;}bool operator==(const mint &p) const { return x == p.x; }bool operator!=(const mint &p) const { return x != p.x; }// for prime modmint inv() const { return pow(mod-2);}mint& operator/=(const mint a) { return *this *= a.inv();}mint operator/(const mint a) const { return mint(*this) /= a;}};istream& operator>>(istream& is, mint& a) { return is >> a.x;}ostream& operator<<(ostream& os, const mint& a) { return os << a.x;}using vm=vector<mint>;using vvm=vector<vm>;struct combination {vector<mint> fact, ifact;combination(int n):fact(n+1),ifact(n+1) {assert(n < mod);fact[0] = 1;for (int i = 1; i <= n; ++i) fact[i] = fact[i-1]*i;ifact[n] = fact[n].inv();for (int i = n; i >= 1; --i) ifact[i-1] = ifact[i]*i;}mint operator()(int n, int k) {if (k < 0 || k > n) return 0;return fact[n]*ifact[k]*ifact[n-k];}}comb(max_n);//0-indexed,2冪のセグメントツリーtemplate <class T>struct SegTree {private:int n;// 葉の数vector<T> data;// データを格納するvectorT def; // 初期値かつ単位元function<T(T, T)> operation; // 区間クエリで使う処理function<T(T, T)> change;// 点更新で使う処理T find(int a, int b) {T val_left = def, val_right = def;for (a += (n - 1), b += (n - 1); a < b; a >>= 1, b >>= 1){if ((a & 1) == 0){val_left = operation(val_left, data[a]);}if ((b & 1) == 0){val_right = operation(data[--b],val_right);}}return operation(val_left, val_right);}public:// _n:必要サイズ, _def:初期値かつ単位元, _operation:クエリ関数,// _change:更新関数SegTree(size_t _n, T _def, function<T(T, T)> _operation,function<T(T, T)> _change=[](T a,T b){return b;}): def(_def), operation(_operation), change(_change) {n = 1;while (n < _n) {n *= 2;}data = vector<T>(2 * n - 1, def);}void set(int i, T x) { data[i + n - 1] = x; }void build() {for (int k=n-2;k>=0;k--) data[k] = operation(data[2*k+1],data[2*k+2]);}// 場所i(0-indexed)の値をxで更新void update(int i, T x) {i += n - 1;data[i] = change(data[i], x);while (i > 0) {i = (i - 1) / 2;data[i] = operation(data[i * 2 + 1], data[i * 2 + 2]);}}T all_prod(){return data[0];}// [a, b)の区間クエリを実行T query(int a, int b) {//return _query(a, b, 0, 0, n);return find(a,b);}// 添字でアクセスT operator[](int i) {return data[i + n - 1];}};int main(){ll n;cin >> n;SegTree<mint> st(n,0,[](mint a,mint b){return a+b;});//SegTree<mint> cand(n,0,[](mint a,mint b){return a+b;});vl p(n);rep(i,n)cin >> p[i],p[i]--;mint sum=0;rep(i,n){//ll prec=n-i-2;if(prec<0)prec=0;sum+=st.query(p[i],n)/mint(2).pow(i);st.update(p[i],mint(2).pow(n-1+i));//cand.update(p[i],mint(2).pow(i));}//cout << sum << endl;rep(i,n)st.update(i,0);mint inv=0;rep(i,n){inv+=st.query(p[i],n);st.update(p[i],1);}cout << inv*mint(2).pow(n-1)-sum << endl;}