Submission #1111562

#	Time	Username	Problem	Language	Result	Execution time	Memory
1111562		Ruichen	Fire (BOI24_fire)	C++17	0 / 100	1 ms	516 KiB

Main

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

struct shift{
	int s, e;
	const bool operator<(const shift &t) const{if(s==t.s){return e<t.e;}return s<t.s;}
};

int main(){
	int n, m, li, lt=0;
	cin >> n >> m;
	vector<shift> v(n);
	for(int i=0; i<n; i++){
		cin >> v[i].s >> v[i].e;
	}
	sort(v.begin(),v.end());
	for(int i=0; i<n; i++){
		if((v[i].e-v[i].s+m)%m>lt){
			lt=(v[i].e-v[i].s+m)%m;
			li=i;
		}
	}
	priority_queue<int> pq;
	if(v[li].e<v[li].s){
		v[li].e+=m;
	}
	int pf=v[li].e, p=(li+1)%n, ans=1;
	while(pf<v[li].s+m){
		while(v[p].s<=pf&&p<li){
			if((v[p].s<v[li].s&&v[p].s+m<=pf)||v[p].s>v[li].s){
				if(v[p].e<v[li].s||v[p].s<v[li].s){
					pq.push(v[p].e+m);
				}
				else{
					pq.push(v[p].e);
				}
				//cout << p << " " << v[p].e << " " << pf << endl;
				p++;
				p%=n;
			}
			else{
				break;
			}
		}
		if(pq.empty()||pq.top()<=pf){
			cout << -1 << endl;
			return 0;
		}
		else{
			ans++;
			pf=pq.top();
			pq.pop();
		}
	}
	cout << ans << endl;
	return 0;
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:29:19: warning: 'li' may be used uninitialized in this function [-Wmaybe-uninitialized]
   29 |   while(v[p].s<=pf&&p<li){

• Subtask 1: 0 / 14
• Subtask 2: 0 / 17
• Subtask 3: 0 / 9
• Subtask 4: 0 / 13
• Subtask 5: 0 / 21
• Subtask 6: 0 / 26