Submission #893493

#	Time	Username	Problem	Language	Result	Execution time	Memory
893493		abushbandit_1	Road Construction (JOI21_road_construction)	C++17	38 / 100	7753 ms	661512 KiB

road_construction

/*

author : abushbandit

platform : vjudge

date : 27.12.2023

contest : Izho PREP (contest #8)

problem : A - Road Construction

for subtask 1,2,3 !!!

*/


#include <bits/stdc++.h>

using namespace std;

#define int long long
#define pb push_back
#define all(x) x.begin(),x.end()
#define ff first
#define ss second

const long long INF = 1e18;
const int N = 1e5 + 1;
 
vector<pair<int, int>> a;
multiset<int> ans;
map<pair<pair<int,int>,pair<int,int>>,bool> vis;
int mn = INF;
int n,k;
 
int dist(pair<int, int> f, pair<int, int> s){
    return abs(f.ff - s.ff) + abs(f.ss - s.ss);
}
 
void update(pair<int, int> f, pair<int, int> s){
	if(vis[{f,s}] || vis[{s,f}]) return;
    ans.insert(dist(f, s));
    vis[{f,s}] = 1;
    if(ans.size() == k) mn = *(--	ans.end());
    else if(ans.size() > k) {
        ans.erase((--ans.end()));
        mn = *(--ans.end());
    }
}
 
bool cmp(pair<int, int> f, pair<int, int> s){
    return f.ss < s.ss;
}
 
void rec(int l, int r){
    if (r - l <= 3) {
        for (int i = l; i < r; i++) {
            for (int j = i + 1; j <= r; j++) {
                update(a[i], a[j]);
            }
        }
        sort(a.begin() + l, a.begin() + r + 1, cmp);
        return;
    }
 
    int m = (l + r) >> 1;
    int md = a[m].ff;
    rec(l, m), rec(m + 1, r);
    vector<pair<int, int>> t(r - l + 1);
    merge(a.begin() + l, a.begin() + m + 1, a.begin() + m + 1, a.begin() + r + 1, t.begin(), cmp);
    copy(t.begin(), t.begin() + r - l + 1, a.begin() + l);
 
    int sz = 0;
    for (int i = l; i <= r; i++) {
        if (abs(a[i].ff - md) < mn) {
            for (int j = sz - 1; j >= 0 && a[i].ss - t[j].ss < mn; j--) {
                update(a[i], t[j]);
            }
            t[sz] = a[i];
            sz++;
        }
    }
}

signed main(){
	
 	
	
    cin >> n >> k;
    int cnt = 0;
    for (int i = 0; i < n; i++) {
        int x, y;
        cin >> x >> y;
        if(y == 0){
        	cnt++;
		}
        a.pb({x, y});
    }
    if(cnt == n || 	n <= 100000){
	    sort(all(a));
	    rec(0, n - 1);
	    for(auto i : ans){
	    	cout << i << "\n";
		}	
	} else{
		int cnt1 = 0;
	 	for(int i = 0;i < 1e18;i++){
	 		cnt1++;
		}
	}								
}	

Compilation message (stderr)

road_construction.cpp: In function 'void update(std::pair<long long int, long long int>, std::pair<long long int, long long int>)':
road_construction.cpp:45:19: warning: comparison of integer expressions of different signedness: 'std::multiset<long long int>::size_type' {aka 'long unsigned int'} and 'long long int' [-Wsign-compare]
   45 |     if(ans.size() == k) mn = *(-- ans.end());
      |        ~~~~~~~~~~~^~~~
road_construction.cpp:46:24: warning: comparison of integer expressions of different signedness: 'std::multiset<long long int>::size_type' {aka 'long unsigned int'} and 'long long int' [-Wsign-compare]
   46 |     else if(ans.size() > k) {
      |             ~~~~~~~~~~~^~~

• Subtask 1: 5 / 5
• Subtask 2: 6 / 6
• Subtask 3: 0 / 7
• Subtask 4: 0 / 20
• Subtask 5: 27 / 27
• Subtask 6: 0 / 35