Submission #1164999

#	Time	Username	Problem	Language	Result	Execution time	Memory
1164999		pinbu	Advertisement 2 (JOI23_ho_t2)	C++20	100 / 100	157 ms	17156 KiB

Main

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

const int N = 500005;
const long long oo = 1e18;

int n;
array<int, 3> a[N], b[N];
vector<int> idas, idbs;
void solve(void) {
	cin >> n;
	for (int i = 1, x, e; i <= n; i++) {
		cin >> x >> e;
		a[i] = {x, x + e, i}; b[i] = {x, x - e, i};
	}
	sort(a + 1, a + 1 + n, [&] (const array<int, 3> &X, const array<int, 3> &Y) {
		return X[0] < Y[0] || (X[0] == Y[0] && (X[1] > Y[1] || (X[1] == Y[1] && X[2] < Y[2])));
	});
	sort(b + 1, b + 1 + n, [&] (const array<int, 3> &X, const array<int, 3> &Y) {
		return X[0] < Y[0] || (X[0] == Y[0] && (X[1] > Y[1] || (X[1] == Y[1] && X[2] < Y[2])));
	});
	for (int i = n; i; i--) {
		if (idas.empty() || a[i][1] ^ a[idas.back()][1] || a[i][0] ^ a[idas.back()][0]) {
			while (!idas.empty() && (a[i][1] >= a[idas.back()][1] || (a[i][1] == a[idas.back()][1] && a[i][0] ^ a[idas.back()][0]))) idas.pop_back();
			idas.emplace_back(i);
		}
	}
	reverse(begin(idas), end(idas));
	for (int i = 1; i <= n; i++) {
		while (!idbs.empty() && b[i][1] <= b[idbs.back()][1]) idbs.pop_back();
		idbs.emplace_back(i);
	}
	int ans = 0;
	for (int i = 0, j = 0; i < (int)idas.size() && j < (int)idbs.size();) {
		int i1 = idas[i], i2 = idbs[j];
		if (a[i1][0] < b[i2][0]) i++;
		else if (a[i1][0] > b[i2][0]) j++;
		else {
			ans += (a[i1][2] == b[i2][2]);
			i++;
			j++;
		}
	}
	cout << ans;
}

signed main(void) {
    ios::sync_with_stdio(false); cin.tie(nullptr);
    
    solve();
    
    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 23 / 23
• Subtask 3: 36 / 36
• Subtask 4: 31 / 31