Submission #645383

#	Time	Username	Problem	Language	Result	Execution time	Memory
645383		gun_gan	Lasers (NOI19_lasers)	C++17	41 / 100	1097 ms	31784 KiB

lasers

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

const int N = 5e5 + 5;
int l, r;
vector<int> s[N];

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

	cin >> l >> r;
	for(int i = 0; i < r; i++) {
		int x; cin >> x;
		for(int j = 0; j < x; j++) {
			int p; cin >> p;
			if(s[i].empty()) s[i].push_back(p);
			else s[i].push_back(s[i].back() + p);
		}
	}
	int ans = l;
	for(int i = 1; i <= l; i++) {
		bool ok = 1;
		for(int j = 0; j < r; j++) {
			auto it = lower_bound(s[j].begin(), s[j].end(), i); 
			int x = (it == s[j].begin() ? 0 : *(--it));
			ok &= l - i >= s[j].back() - x;
		}
		ans -= ok;
	}
	cout << ans << '\n';
}

• Subtask 1: 0 / 10
• Subtask 2: 0 / 14
• Subtask 3: 20 / 20
• Subtask 4: 21 / 21
• Subtask 5: 0 / 22
• Subtask 6: 0 / 13