Submission #423587

#	Time	Username	Problem	Language	Result	Execution time	Memory
423587		JvThunder	Autobahn (COI21_autobahn)	C++14	100 / 100	818 ms	52452 KiB

autobahn

#include <bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define fir first
#define sec second
typedef long long ll;

using namespace std;

int n,k,z;
multiset<pair<pair<int,int>,int>> s;
vector<pair<pair<int,int>,int>> val;
void solve()
{
    cin >> n >> k >> z;
    set<int> all;
    for(int i=0;i<n;i++)
    {
        int l,t,r;
        cin >> l >> t >> r;
        s.insert({{l,l+t-1},0});
        s.insert({{l+t,r},1});
        all.insert(l);
        all.insert(max(1,l+t-z));
        all.insert(l+t-1);
        all.insert(l+t);
        all.insert(max(1,r-z+1));
        all.insert(r);
        all.insert(r+1);
    }

    priority_queue<pair<int,int>> pq;
    int cnt = 0;
    auto itr = s.begin();
    int prv = 0;
    for(auto x:all)
    {
        if(pq.size()>=k) val.pb({{prv,x-1},cnt});
        prv = x;

        while(itr!=s.end() && (*itr).fir.fir<=x)
        {
            if((*itr).sec==1) cnt++;
            pq.push({-(*itr).fir.sec,(*itr).sec});
            itr++;
        }

        while(!pq.empty() && -pq.top().fir<x)
        {
            if(pq.top().sec==1) cnt--;
            pq.pop();
        }
    }

    ll sum = 0;
    ll mxsum = 0;
    int ptr2 = -1;
    for(int ptr=0;ptr<val.size();ptr++)
    {
        while(ptr2+1<val.size() && val[ptr2+1].fir.sec<val[ptr].fir.fir+z)
        {
            ptr2++;
            sum += (ll)val[ptr2].sec*(val[ptr2].fir.sec-val[ptr2].fir.fir+1);
        }
        mxsum = max(mxsum,sum);
        sum -= (ll)val[ptr].sec*(val[ptr].fir.sec-val[ptr].fir.fir+1);
    }
    cout << mxsum << endl;

    return;
}

int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(0); cout.tie(0);
	int tc=1;
	//cin>>tc;
	for(int i=1;i<=tc;i++) solve();
 	return 0;
}

Compilation message (stderr)

autobahn.cpp: In function 'void solve()':
autobahn.cpp:38:21: warning: comparison of integer expressions of different signedness: 'std::priority_queue<std::pair<int, int> >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   38 |         if(pq.size()>=k) val.pb({{prv,x-1},cnt});
      |            ~~~~~~~~~^~~
autobahn.cpp:58:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<std::pair<int, int>, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   58 |     for(int ptr=0;ptr<val.size();ptr++)
      |                   ~~~^~~~~~~~~~~
autobahn.cpp:60:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<std::pair<int, int>, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   60 |         while(ptr2+1<val.size() && val[ptr2+1].fir.sec<val[ptr].fir.fir+z)
      |               ~~~~~~^~~~~~~~~~~

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