[Advanced/C++/1017] Suggestion

[xwcai98]

虽然同样使用了优先队列记录结束时间，但是优先队列其实不需要初始化，我认为以下写法更加优秀。

#include <bits/stdc++.h>
using namespace std;
int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	cout.tie(nullptr);
	const int st = 8 * 3600, en = 17 * 3600;
	int n, k;
	cin >> n >> k;
	vector<pair<int, int>> a;
	for (int i = 0; i < n; ++i) {
		string time;
		int op;
		cin >> time >> op;
		int t = stoi(time.substr(0, 2)) * 3600 + 
			stoi(time.substr(3, 2)) * 60 + stoi(time.substr(6, 2));
		if (t >= en) continue;
		a.emplace_back(t, min(op * 60, 3600));
	}
	sort(a.begin(), a.end());
	int tot = 0, now = st;
	priority_queue<int, vector<int>, greater<int>> q;
	for (auto e: a) {
		now = max(now, e.first);
		while (!q.empty() && q.top() <= now) q.pop();
		if (q.size() == k) {
			now = max(now, q.top());
			q.pop();
		}
		q.push(now + e.second);
		tot += now - e.first;
	}
	int cnt = a.size();
	cout << fixed << setprecision(1) << tot / 60.0 / cnt << '\n';
	return 0;
}