結果

問題 No.1300 Sum of Inversions
ユーザー hedwig100hedwig100
提出日時 2020-11-27 22:47:31
言語 C++14
(gcc 13.3.0 + boost 1.87.0)
結果
AC  
実行時間 342 ms / 2,000 ms
コード長 5,507 bytes
コンパイル時間 2,108 ms
コンパイル使用メモリ 190,180 KB
実行使用メモリ 39,216 KB
最終ジャッジ日時 2024-07-26 19:07:15
合計ジャッジ時間 10,901 ms
ジャッジサーバーID
(参考情報)
judge4 / judge2
このコードへのチャレンジ
(要ログイン)
ファイルパターン 結果
sample AC * 3
other AC * 34
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 #
プレゼンテーションモードにする

#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL_
void debug_out() {cerr << endl;}
template<typename Head,typename... Tail> void debug_out(Head H,Tail... T){cerr << ' ' << H; debug_out(T...);}
#define debug(...) cerr << 'L' << __LINE__ << " [" << #__VA_ARGS__ << "]:",debug_out(__VA_ARGS__)
#define dump(x) cerr << 'L' << __LINE__ << " " << #x << " = " << (x) << endl;
#else
#define debug(...) (void(0))
#define dump(x) (void(0))
#endif
#define rep(i,n) for (int i = 0; i < (int)(n); i ++)
#define irep(i,n) for (int i = (int)(n) - 1;i >= 0;--i)
using ll = long long;
using PL = pair<ll,ll>;
using P = pair<int,int>;
constexpr int INF = 1000000000;
constexpr long long HINF = 100000'00000'00000;
constexpr long long MOD = 998244353;
constexpr double EPS = 1e-4;
constexpr double PI = 3.14159265358979;
#pragma region Macros
template<typename T1,typename T2> ostream &operator<<(ostream &os,const pair<T1,T2> &p) {
os << '(' << p.first << ',' << p.second << ')'; return os;
}
template<typename T> ostream &operator<<(ostream &os,const vector<T> &v) {
os << '[';
for (auto &e:v) {os << e << ',';}
os << ']'; return os;
}
// grid searh
const int dy[8] = {-1,0,1,0,-1,-1,1,1};
const int dx[8] = {0,1,0,-1,-1,1,-1,1};
bool IN(int y,int x,int H,int W) {return (0 <= y)&&(y < H)&&(0 <= x)&&(x < W);}
#pragma endregion
template<class T>
struct BinaryIndexedTree {
int N,power = 1;
vector<T> bit;
BinaryIndexedTree(int N = 0): N(N){
bit.assign(N + 1,0);
while (power <= N) power <<= 1; //power > N
}
void build(const vector<T> &A) {
for (int i = 1;i <= N; ++i) add(i,A[i - 1]);
}
// add x to a[i]
void add(int i,T x) {
for (int idx = i; idx <= N; idx += (idx & -idx)) {
bit[idx] += x;
}
}
// return a[1] + a[2] + a[3] + .. + a[k]
T sum(int k) {
T ret = 0;
for (int idx = k; idx > 0; idx -= (idx & -idx)) {
ret += bit[idx];
}
return ret;
}
// return a[l] + a[l + 1] + a[l + 2] + .. + a[r - 1]
T sum(int l,int r) {
return sum(r - 1) - sum(l - 1);
}
// return min index s.t. a[1] + a[2] + a[3] + .. + a[x] >= w
int lower_bound(T w) {
if (w <= 0) return 0;
int x = 0;
for (int r = power; r > 0; r >>= 1) {
if (x + r <= N && bit[x + r] < w) {
w -= bit[x + r];
x += r;
}
}
return x + 1;
}
};
template<int Modulus>
struct ModInt {
long long x;
ModInt(long long x = 0) :x((x%Modulus + Modulus)%Modulus) {}
constexpr ModInt &operator+=(const ModInt a) {if ((x += a.x) >= Modulus) x -= Modulus; return *this;}
constexpr ModInt &operator-=(const ModInt a) {if ((x += Modulus - a.x) >= Modulus) x -= Modulus; return *this;}
constexpr ModInt &operator*=(const ModInt a) {(x *= a.x) %= Modulus; return *this;}
constexpr ModInt &operator/=(const ModInt a) {return *this *= a.inverse();}
constexpr ModInt operator+(const ModInt a) const {return ModInt(*this) += a.x;}
constexpr ModInt operator-(const ModInt a) const {return ModInt(*this) -= a.x;}
constexpr ModInt operator*(const ModInt a) const {return ModInt(*this) *= a.x;}
constexpr ModInt operator/(const ModInt a) const {return ModInt(*this) /= a.x;}
friend constexpr ostream& operator<<(ostream& os,const ModInt<Modulus>& a) {return os << a.x;}
friend constexpr istream& operator>>(istream& is,ModInt<Modulus>& a) {return is >> a.x;}
ModInt inverse() const {// x ^ (-1)
long long a = x,b = Modulus,p = 1,q = 0;
while (b) {long long d = a/b; a -= d*b; swap(a,b); p -= d*q; swap(p,q);}
return ModInt(p);
}
ModInt pow(long long N) {// x ^ N
ModInt a = 1;
while (N) {
if (N&1) a *= *this;
*this *= *this;
N >>= 1;
}
return a;
}
};
using mint = ModInt<998244353>;
map<ll,int> compress(vector<ll> A) {
sort(A.begin(),A.end());
A.erase(unique(A.begin(),A.end()),A.end());
map<ll,int> mp;
rep(i,A.size()) mp[A[i]] = i;
return mp;
}
int main() {
cin.tie(nullptr);
ios::sync_with_stdio(false);
cout << fixed << setprecision(20);
int N; cin >> N;
vector<ll> A(N);
rep(i,N) cin >> A[i];
auto mp = compress(A);
int M = mp.size();
vector<vector<int>> B(M);
rep(i,N) {
int idx = mp[A[i]];
B[idx].push_back(i);
}
vector<ll> cntL(N),cntR(N);
vector<mint> left(N),right(N);
mint tot = 0;
int bf = 0;
BinaryIndexedTree<mint> bit(N);
BinaryIndexedTree<int> idx(N);
rep(i,M) {
for (int j:B[i]) {
left[j] = tot - bit.sum(j+1);
cntL[j] = bf - idx.sum(j+1);
}
for (int j:B[i]) {
bit.add(j+1,mint(A[j]));
idx.add(j+1,1);
tot += A[j];
++bf;
}
}
BinaryIndexedTree<mint> bit2(N);
BinaryIndexedTree<int> idx2(N);
irep(i,M) {
for (int j:B[i]) {
right[j] = bit2.sum(j+1);
cntR[j] = idx2.sum(j+1);
}
for (int j:B[i]) {
bit2.add(j+1,mint(A[j]));
idx2.add(j+1,1);
}
}
mint ans = 0;
rep(i,N) {
ans += cntL[i]*cntR[i]%MOD*A[i];
if (cntL[i] > 0 && cntR[i] > 0) {
ans += right[i]*cntL[i];
ans += left[i]*cntR[i];
}
}
cout << ans << '\n';
return 0;
}
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
0