Submission #893818

#	Time	Username	Problem	Language	Result	Execution time	Memory
893818		Nurislam	Road Construction (JOI21_road_construction)	C++14	100 / 100	8923 ms	573472 KiB

road_construction

#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define ff first
#define ss second
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define int long long
///*                                                    __                    __                        __                    */
///*        ======     _      /| /|  __   _            /   |  |   /|  |   @  |    |  |  | /   /| |\  | /   |  |  @ | /        */
///* \-       ||  |_| |_     / |/ | |  | |_  |-        |   |--|  /-|  |   |  \ \  |==|  |-   /=| | \ | |   |--|  | |-         */
///*          ||  | | |_    /     | |__|  _| |_        \__ |  | /  |  |__ |  __|  |  |  | \ /  | |  \| \__ |  |  | | \        */
///*  
typedef vector<int> vi;
typedef pair<int,int> pii;
typedef vector<pii> vii;
multiset<int> ans;
const int N = 3e5;
struct pt {
	int x, y, id;
};
map<pii, bool> mp;
pt a[N];
int n, k;
bool cmp_x (const pt & a, const pt & b) {
	return a.x < b.x || (a.x == b.x && a.y < b.y);
}
 
bool cmp_y (const pt & a, const pt & b) {
	return a.y < b.y;
}
double mindist;
int ansa, ansb;
 
void upd_ans (const pt & a, const pt & b) {
	if(mp[{a.id,b.id}])return;
	mp[{a.id, b.id}] = 1;
	mp[{b.id, a.id}] = 1;
	int dist = abs(a.x-b.x) + abs(a.y-b.y);
	ans.insert(dist);
	while((int)ans.size()>k)ans.erase(prev(ans.end()));
	if((int)ans.size()>=k)mindist = *ans.rbegin();
}
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)
				upd_ans (a[i], a[j]);
		sort (a+l, a+r+1, &cmp_y);
		return;
	}
 
	int m = (l + r) >> 1;
	int midx = a[m].x;
	rec (l, m),  rec (m+1, r);
	static pt t[N];
	merge (a+l, a+m+1, a+m+1, a+r+1, t, &cmp_y);
	copy (t, t+r-l+1, a+l);
 
	int tsz = 0;
	for (int i=l; i<=r; ++i)
		if (abs (a[i].x - midx) < mindist) {
			for (int j=tsz-1; j>=0 && a[i].y - t[j].y < mindist; --j)
				upd_ans (a[i], t[j]);
			t[tsz++] = a[i];
		}
}
void solve(){
	cin >> n >> k;
	for (int i = 0; i < n; i++)
	{
		cin >> a[i].x >> a[i].y;
		a[i].id = i;
	}
	sort (a, a+n, &cmp_x);
	mindist = 1e18;
	rec (0, n-1);
	for(auto i:ans){
		cout << i << '\n';
	}
}
main(){
	ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
	int test = 1;
	//~ cin >> test;
	while(test--){
		solve();
	}
}

Compilation message (stderr)

road_construction.cpp:82:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   82 | main(){
      | ^~~~

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