#877798 (C++17) No.2336 Do you like typical problems?

• 問題: No.2336 Do you like typical problems?
• ユーザー: kwm_t
• 提出日時: 2023-06-03 10:51:58
• 言語: C++17 (gcc 12.3.0 + boost 1.83.0)
• 結果: AC
• 実行時間: 554 ms / 2,000 ms
• コード長: 3,468 bytes
• コンパイル時間: 4,410 ms
• コンパイル使用メモリ: 273,724 KB
• 実行使用メモリ: 35,308 KB
• 最終ジャッジ日時: 2023-08-28 07:41:38
• 合計ジャッジ時間: 9,434 ms
• ジャッジサーバーID （参考情報）: judge13 / judge15

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	24 ms; 18,688 KB
testcase_01	AC	24 ms; 18,484 KB
testcase_02	AC	24 ms; 18,612 KB
testcase_03	AC	24 ms; 18,596 KB
testcase_04	AC	25 ms; 18,512 KB
testcase_05	AC	24 ms; 18,644 KB
testcase_06	AC	24 ms; 18,800 KB
testcase_07	AC	24 ms; 18,768 KB
testcase_08	AC	27 ms; 18,916 KB
testcase_09	AC	27 ms; 18,968 KB
testcase_10	AC	29 ms; 18,940 KB
testcase_11	AC	29 ms; 18,980 KB
testcase_12	AC	28 ms; 19,008 KB
testcase_13	AC	545 ms; 35,216 KB
testcase_14	AC	548 ms; 35,176 KB
testcase_15	AC	549 ms; 35,216 KB
testcase_16	AC	545 ms; 35,276 KB
testcase_17	AC	554 ms; 35,308 KB
testcase_18	AC	89 ms; 22,344 KB
testcase_19	AC	102 ms; 22,308 KB
testcase_20	AC	446 ms; 35,288 KB

ソースコード

#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
//using mint = modint1000000007;
//const int mod = 1000000007;
using mint = modint998244353;
const int mod = 998244353;
//const int INF = 1e9;
//const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n-1); i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r-1);i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define endl "\n"
#define P pair<int,int>
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }
// combination mod prime
// https://www.youtube.com/watch?v=8uowVvQ_-Mo&feature=youtu.be&t=1619
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) { return com(n, k); }
	mint com(int n, int k) {
		//負の二項係数を考慮する場合にコメントアウトを外す
		//if (n < 0) return com(-n, k) * (k % 2 ? -1 : 1);
		if (k < 0 || k > n) return 0;
		return fact[n] * ifact[k] * ifact[n - k];
	}
	mint comsub(long long n, long long k) {
		if (n - k < k) k = n - k;
		assert(k < fact.size());
		mint val = ifact[k];
		rep(i, k) val *= n - i;
		return val;
	}
	mint inv(int n, int k) {
		//if (n < 0) return inv(-n, k) * (k % 2 ? -1 : 1);
		if (k < 0 || k > n) return 0;
		return ifact[n] * fact[k] * fact[n - k];
	}
	mint p(int n, int k) { return fact[n] * ifact[n - k]; }
}c(2000006);
template <class S>
struct value_compression : vector<S> {
	bool built = false;
	using VS = vector<S>;
	using VS::VS;
	value_compression(vector<S> v = {}) : vector<S>(move(v)) {}
	void build() {
		sort(this->begin(), this->end());
		this->erase(unique(this->begin(), this->end()), this->end());
		built = true;
	}
	template <class T>
	void convert(T first, T last) {
		assert(built);
		for (; first != last; ++first) *first = (*this)(*first);
	}
	int operator()(S x) {
		assert(built);
		return lower_bound(this->begin(), this->end(), x) - this->begin();
	}
	void clear() {
		this->clear();
		built = false;
	}
};
struct S {
	mint val;
	int size;
};
using F = mint;
S op(S sl, S sr) { return S{ sl.val + sr.val, sl.size + sr.size }; }
S e() { return S{ 0, 0 }; }
S mapping(F f, S x) { return S{ x.val + x.size * f, x.size }; }
F composition(F f, F g) { return F{ f + g }; }
F id() { return 0; }
int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int n; cin >> n;
	vector<P>bc(n);
	value_compression<int> vc;
	rep(i, n) {
		cin >> bc[i].first >> bc[i].second;
		bc[i].first--;
		vc.emplace_back(bc[i].first);
		vc.emplace_back(bc[i].second);
	}
	vc.build();
	int sz = int(vc.size()) - 1;
	vector<S> v(sz);
	rep(i, sz) {
		v[i] = S{ 0,vc[i + 1] - vc[i] };
	}
	lazy_segtree<S, op, e, F, mapping, composition, id> seg(v);
	mint ans = c(n, 2);
	for (auto[b, c] : bc) {
		int l = vc(b);
		int r = vc(c);
		int sz = c - b;
		mint inv = mint(sz).inv();
		ans -= seg.prod(l, r).val * inv;
		seg.apply(l, r, inv);
	}
	ans *= c.fact[n];
	ans /= 2;
	cout << ans.val() << endl;
	return 0;
}