Submission #505041

#	Time	Username	Problem	Language	Result	Execution time	Memory
505041		Jarif_Rahman	여별 열쇠 (JOI15_keys)	C++17	10 / 100	1084 ms	336 KiB

keys

#include <bits/stdc++.h>
#define pb push_back
#define f first
#define sc second
using namespace std;
typedef long long int ll;
typedef string str;
const int inf = 1e9+1;

int mn = inf;
int n, m, k;

vector<pair<int, int>> events;
vector<pair<int, int>> pp;
vector<pair<int, int>> ss;

void bf(int in){
    if(in == n){
        if(ss.size() != k) return;
        set<int> s;
        for(int i = 0; i < k; i++) s.insert(ss[i].f), s.insert(ss[i].sc);
        int cur = 0;
        for(int i: s) cur+=events[i+1].f-events[i].f;
        mn = min(mn, cur);
        return;
    }
    ss.pb(pp[in]);
    bf(in+1);
    ss.pop_back();
    bf(in+1);
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin >> n >> m >> k;
    k = n-k;

    for(int i = 0; i < n; i++){
        int x, y; cin >> x >> y; 
        events.pb({x, i+1});
        events.pb({y, -i-1});
    }

    sort(events.begin(), events.end());
    pp.resize(n);
    for(int i = 0; i < 2*n; i++){
        if(events[i].sc > 0) pp[events[i].sc-1].f = i;
        else pp[-events[i].sc-1].sc = i-1;
    }

    int ans = m;

    bf(0);

    ans-=mn;

    cout << ans << "\n";
}

Compilation message (stderr)

keys.cpp: In function 'void bf(int)':
keys.cpp:19:22: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   19 |         if(ss.size() != k) return;
      |            ~~~~~~~~~~^~~~

• Subtask 1: 10 / 10
• Subtask 2: 0 / 90