제출 #1220750

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1220750		HappyCapybara	도시들 (IOI15_towns)	C++20	0 / 100	10 ms	328 KiB

towns

#include "towns.h"
#include<bits/stdc++.h>
using namespace std;

map<pair<int,int>,int> res;

int getDist(int a, int b){
	if (a == b) return 0;
	if (a > b) swap(a, b);
	if (res.find({a, b}) == res.end()) res[{a, b}] = getDistance(a, b);
	return res[{a, b}];
}

int hubDistance(int N, int sub) {
	vector<int> d1(N, 0), d2(N, 0);
	int bsf = 0, f1, f2;
	for (int i=1; i<N; i++){
		int d = getDist(0, i);
		if (d > bsf){
			bsf = d;
			f1 = i;
		}
	}
	bsf = 0;
	for (int i=0; i<N; i++){
		if (i == f1) continue;
		int d = getDist(f1, i);
		d1[i] = d;
		if (d > bsf){
			bsf = d;
			f2 = i;
		}
	}
	int R = pow(10, 9);
	map<int,vector<int>> m;
	for (int i=0; i<N; i++){
		if (i == f1 || i == f2) continue;
		int d = getDist(f2, i);
		d2[i] = d;
		int l = (d1[i]+d2[i]-bsf)/2;
		R = min(R, max(d1[i], d2[i])-l);
		m[d1[i]-l].push_back(i);
	}
	bool bal = false;
	for (auto it=m.begin(); it != m.end(); it++){
		if (it->first == R || it->first == bsf-R){
			int x1 = 1, x2 = 0, x3 = 1;
			for (auto jt=m.begin(); jt != it; jt++) x1 += jt->second.size();
			for (auto jt=next(it); jt != m.end(); jt++) x3 += jt->second.size();
			set<pair<int,int>> s, d;
			for (int v : it->second) s.insert({1, v});
			while (s.size() > 1){
				if (s.size() % 2){
					d.insert(*s.begin());
					s.erase(s.begin());
				}
				set<pair<int,int>> ns;
				while (!s.empty()){
					auto g1 = s.begin(), g2 = next(s.begin());
					if (d1[g1->second]+d1[g2->second]-getDist(g1->second, g2->second) > 2*it->first) ns.insert({g1->first+g2->first, g1->second});
					else {
						d.insert(*g1);
						d.insert(*g2);
					}
					s.erase(s.begin());
					s.erase(s.begin());
				}
				s = ns;
			}
			if (!s.empty()){
				x2 = s.begin()->first;
				for (auto [num, rep] : d){
					if (d1[s.begin()->second]+d1[rep]-getDist(s.begin()->second, rep) > 2*it->first) x2 += num;
				}
			}
			//cout << x1 << " " << x2 << " " << x3 << endl;
			if (x1 <= N/2 && x2 <= N/2 && x3 <= N/2) bal = true;
		}
	}
	if (bal) return R;
	else return -R;
}

• Subtask 1: 0 / 13
• Subtask 2: 0 / 12
• Subtask 3: 0 / 13
• Subtask 4: 0 / 10
• Subtask 5: 0 / 13
• Subtask 6: 0 / 39