Submission #4544875

---

Source Code Expand

#include <bits/stdc++.h>
using namespace std;

using VS = vector<string>;    using LL = long long;
using VI = vector<int>;       using VVI = vector<VI>;
using PII = pair<int, int>;   using PLL = pair<LL, LL>;
using VL = vector<LL>;        using VVL = vector<VL>;

#define ALL(a)  begin((a)),end((a))
#define RALL(a) (a).rbegin(), (a).rend()
#define SZ(a) int((a).size())
#define SORT(c) sort(ALL((c)))
#define RSORT(c) sort(RALL((c)))
#define UNIQ(c) (c).erase(unique(ALL((c))), end((c)))
#define FOR(i, s, e) for (int(i) = (s); (i) < (e); (i)++)
#define FORR(i, s, e) for (int(i) = (s); (i) > (e); (i)--)
//#pragma GCC optimize ("-O3") 
#ifdef YANG33
#include "mydebug.hpp"
#else
#define DD(x) 
#endif
const int INF = 1e9;                          const LL LINF = 1e16;
const LL MOD = 1000000007;                    const double PI = acos(-1.0);
int DX[8] = { 0, 0, 1, -1, 1, 1, -1, -1 };    int DY[8] = { 1, -1, 0, 0, 1, -1, 1, -1 };

/* -----  2019/03/11  Problem: ABC 091 C / Link: http://abc091.contest.atcoder.jp/tasks/abc091_c  ----- */


int main() {
	cin.tie(0);
	ios_base::sync_with_stdio(false);

	LL N; cin >> N;
	using tp = tuple<int, int, int>;
	vector<tp>events;
	FOR(i, 0, N) {
		LL x, y; cin >> x >> y;
		events.push_back(tp(x, y, 0));
	}

	FOR(i, 0, N) {
		LL x, y; cin >> x >> y;
		events.push_back(tp(x, y, 1));
	}
	SORT(events);
	multiset<int>Reds;
	LL ans = 0;
	for (auto e : events) {
		int x, y, id;
		tie(x, y, id) = e;
		if (id) { // blue
			auto it = Reds.lower_bound(y); 
			if (it != Reds.begin()) {
				it--;
				ans++;
				Reds.erase(it);
			}
		}
		else {
			Reds.insert(y);
		}
	}

	cout << (ans) << "\n";

	return 0;
}

Submission Info

Judge Result