제출 #1220783

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1220783		HappyCapybara	도시들 (IOI15_towns)	C++20	13 / 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){
	res.clear();
	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;
	int nh = 0, ih = 0;
	for (auto it=m.begin(); it != m.end(); it++){
		if (it->first == R || it->first == bsf-R){
			nh++;
			int x1 = 1, x2 = it->second.size(), 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();
			if (x1 <= N/2 && x2 <= N/2 && x3 <= N/2) bal = true;
			if (x1 > N/2 || x3 > N/2) ih++;
		}
	}
	if (nh == ih) return -R;
	if (bal == true) return R;
	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();
			if (x1 > N/2 || x3 > N/2) continue;
			vector<int> l1, l2;
			for (int v : it->second){
				if (l1.empty()) l1.push_back(v);
				if (d1[v]+d1[l1.back()]-getDist(v, l1.back()) > 2*it->first) l2.push_back(v);
				else {
					l1.push_back(v);
					if (!l2.empty()){
						l1.push_back(l2.back());
						l2.pop_back();
					}
				}
			}
			int pm = l1.back();
			while (!l1.empty()){
				if (d1[pm]+d1[l1.back()]-getDist(pm, l1.back()) > 2*it->first){
					if (l1.size() == 1){
						l2.push_back(l1.back());
						l1.pop_back();
					}
					else {
						l1.pop_back();
						l1.pop_back();
					}
				}
				else {
					l1.pop_back();
					if (l2.empty()) break;
					l2.pop_back();
				}
			}
			//cout << x1 << " " << x2 << " " << x3 << endl;
			if (l2.empty()) bal = true;
		}
	}
	if (bal) return R;
	else return -R;
}

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