結果

問題 No.2327 Inversion Sum
ユーザー dyktr_06
提出日時 2023-05-09 21:13:49
言語 C++17
(gcc 13.3.0 + boost 1.87.0)
結果
AC  
実行時間 25 ms / 2,000 ms
コード長 6,595 bytes
コンパイル時間 2,246 ms
コンパイル使用メモリ 201,840 KB
最終ジャッジ日時 2025-02-12 21:05:24
ジャッジサーバーID
(参考情報)
judge3 / judge3
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 * 30
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;
template <long long Modulus>
struct ModInt{
long long val;
constexpr ModInt(const long long &_val = 0) noexcept : val(_val) {
normalize();
}
void normalize(){
val = (val % Modulus + Modulus) % Modulus;
}
inline ModInt& operator+=(const ModInt& rhs) noexcept {
if(val += rhs.val, val >= Modulus) val -= Modulus;
return *this;
}
inline ModInt& operator-=(const ModInt& rhs) noexcept {
if(val -= rhs.val, val < 0) val += Modulus;
return *this;
}
inline ModInt& operator*=(const ModInt& rhs) noexcept {
val = val * rhs.val % Modulus;
return *this;
}
inline ModInt& operator/=(const ModInt& rhs) noexcept {
val = val * inv(rhs.val).val % Modulus;
return *this;
}
inline ModInt& operator++() noexcept {
if(++val >= Modulus) val -= Modulus;
return *this;
}
inline ModInt operator++(int) noexcept {
ModInt t = val;
if(++val >= Modulus) val -= Modulus;
return t;
}
inline ModInt& operator--() noexcept {
if(--val < 0) val += Modulus;
return *this;
}
inline ModInt operator--(int) noexcept {
ModInt t = val;
if(--val < 0) val += Modulus;
return t;
}
inline ModInt operator-() const noexcept { return (Modulus - val) % Modulus; }
inline ModInt inv(void) const { return inv(val); }
ModInt inv(const long long& n) const {
long long a = n, b = Modulus, u = 1, v = 0;
while(b){
long long t = a / b;
a -= t * b; swap(a, b);
u -= t * v; swap(u, v);
}
u %= Modulus;
if(u < 0) u += Modulus;
return u;
}
friend inline ModInt operator+(const ModInt& lhs, const ModInt& rhs) noexcept { return ModInt(lhs) += rhs; }
friend inline ModInt operator-(const ModInt& lhs, const ModInt& rhs) noexcept { return ModInt(lhs) -= rhs; }
friend inline ModInt operator*(const ModInt& lhs, const ModInt& rhs) noexcept { return ModInt(lhs) *= rhs; }
friend inline ModInt operator/(const ModInt& lhs, const ModInt& rhs) noexcept { return ModInt(lhs) /= rhs; }
friend inline bool operator==(const ModInt& lhs, const ModInt& rhs) noexcept { return lhs.val == rhs.val; }
friend inline bool operator!=(const ModInt& lhs, const ModInt& rhs) noexcept { return lhs.val != rhs.val; }
friend inline istream& operator>>(istream& is, ModInt& x) noexcept {
is >> x.val;
x.normalize();
return is;
}
friend inline ostream& operator<<(ostream& os, const ModInt& x) noexcept { return os << x.val; }
};
struct Combination{
vector<long long> memo, memoinv, inv;
const long long mod;
Combination(const int &N, const long long &m) : memo(N + 1), memoinv(N + 1), inv(N + 1), mod(m){
memo[0] = memo[1] = 1;
memoinv[0] = memoinv[1] = 1;
inv[1] = 1;
for(int i = 2; i <= N; ++i){
memo[i] = memo[i - 1] * i % mod;
inv[i] = mod - inv[mod % i] * (m / i) % mod;
memoinv[i] = memoinv[i - 1] * inv[i] % mod;
}
}
inline long long fact(const long long &n) const {
return memo[n];
}
inline long long factinv(const long long &n) const {
return memoinv[n];
}
inline long long ncr(const long long &n, const long long &r) const {
if(n < r || r < 0) return 0;
return (memo[n] * memoinv[r] % mod) * memoinv[n - r] % mod;
}
inline long long npr(const long long &n, const long long &r) const {
if(n < r || r < 0) return 0;
return (memo[n] % mod) * memoinv[n - r] % mod;
}
inline long long nhr(const long long &n, const long long &r) const {
if(n == 0 && r == 0) return 1;
return ncr(n + r - 1, r);
}
};
template <typename T>
struct BinaryIndexedTree{
int N;
vector<T> BIT;
BinaryIndexedTree(const int &N): N(N), BIT(N + 1, 0){
}
T get(int i){
return sum(i + 1) - sum(i);
}
void add(int i, T x){
i++;
while(i <= N){
BIT[i] += x;
i += i & -i;
}
}
T sum(int i) const {
T ans = 0;
while(i > 0){
ans += BIT[i];
i -= i & -i;
}
return ans;
}
T sum(int L, int R) const {
return sum(R) - sum(L);
}
int lower_bound(T x) const {
if(x <= 0){
return 0;
}else{
int v = 0, r = 1;
while(r < N) r = r << 1;
for(int len = r; len > 0; len = len >> 1){
if(v + len < N && BIT[v + len] < x){
x -= BIT[v + len];
v += len;
}
}
return v;
}
}
int upper_bound(T x) const {
if(x < 0){
return 0;
}else{
int v = 0, r = 1;
while(r <= N) r = r << 1;
for(int len = r; len > 0; len = len >> 1){
if(v + len <= N && BIT[v + len] <= x){
x -= BIT[v + len];
v += len;
}
}
return v;
}
}
};
const long long MOD = 998244353;
using mint = ModInt<998244353>;
int main(){
ios::sync_with_stdio(false);
cin.tie(nullptr);
int n, m; cin >> n >> m;
vector<int> c(n, -1), check(n, 1);
for(int i = 0; i < m; i++){
int p, k; cin >> p >> k;
p--, k--;
c[k] = p;
check[p] = 0;
}
vector<int> sum_c(n + 1), sum_check(n + 1);
for(int i = 0; i < n; i++) sum_c[i + 1] = sum_c[i] + (c[i] != -1);
for(int i = 0; i < n; i++) sum_check[i + 1] = sum_check[i] + (check[i]);
BinaryIndexedTree<mint> BIT(n);
Combination comb(n, MOD);
mint ans = 0;
mint cntc = 0, cntnc = 0;
for(int i = 0; i < n; i++){
if(check[i]){
cntnc += sum_check[n] - sum_check[i + 1];
}
}
for(int i = 0; i < n; i++){
if(c[i] == -1){
mint plus = comb.fact(n - m - 2);
plus *= i - sum_c[i];
plus *= cntnc;
ans += plus;
ans += cntc * comb.fact(n - m - 1);
}else{
mint plus = sum_check[n] - sum_check[c[i]];
plus *= comb.fact(n - m - 1);
plus *= i - sum_c[i];
ans += plus;
ans += BIT.sum(c[i] + 1, n) * comb.fact(n - m);
cntc += sum_check[c[i]];
BIT.add(c[i], 1);
}
}
cout << ans << endl;
}
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
0