Submission #434913

#	Time	Username	Problem	Language	Result	Execution time	Memory
434913		dqhungdl	Autobahn (COI21_autobahn)	C++17	0 / 100	2 ms	296 KiB

autobahn

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

typedef pair<int,int> ii;
int N,K,X;
vector<ii> events,overtime,charge;

int32_t main() {
#ifdef ACM
	freopen("input","r",stdin);
#endif
	cin>>N>>K>>X;
	int l,t,r;
	for(int i=0;i<N;i++) {
		cin>>l>>t>>r;
		if(l+t<=r) {
			overtime.push_back({l+t,1});
			overtime.push_back({r+1,-1});
		}
		events.push_back({l,1});
		events.push_back({r+1,-1});
	}
	sort(events.begin(),events.end());
	int people=0,pivot;
	for(ii event:events) {
		people+=event.second;
		if(event.second==1&&people==K)
			pivot=event.first;
		else if(event.second==-1&&people==K-1) {
			overtime.push_back({pivot,2});
			overtime.push_back({event.first,-2});
		}
	}
	sort(overtime.begin(),overtime.end());
	//for(ii tmp:overtime)
	//	cerr<<tmp.first<<' '<<tmp.second<<'\n';
	int numOvertime=0;
	bool overload=false;
	for(ii event:overtime) {
		if(abs(event.second)==1)
			numOvertime+=event.second;
		else
			overload=(event.second==2);
		if(overload) {
			if(charge.size()>0&&charge.back().first==event.first)
				charge.back().second=numOvertime;
			else
				charge.push_back({event.first,numOvertime});
		}
		else if(charge.size()>0&&charge.back().first==event.first)
			charge.back().second=0;
		else
			charge.push_back({event.first,0});
	}
	//for(ii tmp:charge)
	//	cerr<<tmp.first<<' '<<tmp.second<<'\n';
	vector<int> S(charge.size());
	for(int i=0;i<charge.size()-1;i++) {
		S[i]=(charge[i+1].first-charge[i].first)*charge[i].second;
		if(i>0)
			S[i]+=S[i-1];
	}
	int cur=0,rs=0;
	for(int i=0;i<charge.size()-1;i++) {
		while(cur<charge.size()-1&&charge[cur+1].first<=charge[i].first+X-1)
			cur++;
		int sum=0;
		if(cur>0)
			sum=S[cur-1]-(i==0?0:S[i-1]);
		sum+=(charge[i].first+X-charge[cur].first)*charge[cur].second;
		rs=max(rs,sum);
	}
	cur=0;
	for(int i=0;i<charge.size()-1;i++) {
		while(cur<i&&charge[cur].first+X<charge[i+1].first)
			cur++;
		int sum=S[i]-S[cur];
		if(cur>0)
			sum+=(charge[cur].first-charge[i+1].first+X)*charge[cur-1].second;
		rs=max(rs,sum);
	}
	cout<<rs;
}

Compilation message (stderr)

autobahn.cpp: In function 'int32_t main()':
autobahn.cpp:59:15: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   59 |  for(int i=0;i<charge.size()-1;i++) {
      |              ~^~~~~~~~~~~~~~~~
autobahn.cpp:65:15: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   65 |  for(int i=0;i<charge.size()-1;i++) {
      |              ~^~~~~~~~~~~~~~~~
autobahn.cpp:66:12: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   66 |   while(cur<charge.size()-1&&charge[cur+1].first<=charge[i].first+X-1)
      |         ~~~^~~~~~~~~~~~~~~~
autobahn.cpp:75:15: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   75 |  for(int i=0;i<charge.size()-1;i++) {
      |              ~^~~~~~~~~~~~~~~~

• Subtask 1: 0 / 20
• Subtask 2: 0 / 30
• Subtask 3: 0 / 50