Submission #1014838

#	Time	Username	Problem	Language	Result	Execution time	Memory
1014838		alex_2008	Split the Attractions (IOI19_split)	C++14	18 / 100	653 ms	1048576 KiB

split

#include "split.h"
#include <iostream>
#include <cmath>
#include <vector>
#include <set>
#include <map>
#include <algorithm>
#include <queue>
using namespace std;
typedef long long ll;
const int N = 1e5 + 10, M = 110;
bool used[N];
int subtree[N];
int par[N];
vector <vector<int>> G;
int sz;
vector <int> esim;
void dfs(int v) {
	if (used[v]) return;
	if ((int)esim.size() == sz) return;
	esim.push_back(v);
	used[v] = true;
	for (auto it : G[v]) {
		dfs(it);
	}
}
void dfss(int v, int p) {
	par[v] = p;
	subtree[v] = 1;
	for (auto it : G[v]) {
		if (it == p) continue;
		dfss(it, v);
		subtree[v] += subtree[it];
	}
}
vector<int> find_split(int n, int A, int B, int C, vector<int> p, vector<int> q) {
	int m = (int)p.size();
	bool sb1 = true, sb2 = true;
	G.resize(n);
	for (int i = 0; i < m; i++) {
		G[p[i]].push_back(q[i]);
		G[q[i]].push_back(p[i]);
	}
	for (int i = 0; i < n; i++) {
		if ((int)G[i].size() > 2) sb1 = false;
	}
	if (sb1) {
		int a = -1, b = -1;
		for (int i = 0; i < n; i++) {
			if ((int)G[i].size() == 1) {
				if (a == -1) a = i;
				else b = i;
			}
		}
		if (a == -1) a = 0;
		vector <int> v;
		v.push_back(a);
		v.push_back(G[a][0]);
		while ((int)v.size() < n) {
			int a = v[(int)v.size() - 1];
			int b = v[(int)v.size() - 2];
			if (G[a][0] == b) v.push_back(G[a][1]);
			else v.push_back(G[a][0]);
		}
		vector <int> ans(n);
		for (int i = 0; i < n; i++) {
			if (i < A) ans[v[i]] = 1;
			else if (i < A + B) ans[v[i]] = 2;
			else ans[v[i]] = 3;
		}
		return ans;
	}
	sb2 = (A == 1);
	if (sb2) {
		sz = B;
		dfs(0);
		vector <int> ans(n);
		bool al = true;
		for (int i = 0; i < n; i++) {
			if (used[i]) ans[i] = 2;
			else {
				if (al) {
					al = false;
					ans[i] = 1;
				}
				else ans[i] = 3;
			}
		}
		return ans;
	}
	vector <pair<int, int>> v = { { A, 1 }, { B, 2 }, { C, 3 } };
	sort(v.begin(), v.end());
	dfss(0, 0);
	bool ch = true;
	if (ch) {
		set <pair<int, int>> candidates;
		for (auto it : G[0]) {
			candidates.insert({ subtree[it], it });
		}
		vector <int> f = { 0 };
		int cur_sz = 1;
		while (cur_sz < v[0].first) {
			auto it = candidates.begin();
			int v = it->second;
			f.push_back(v);
			for (auto it : G[v]) {
				if (it == par[v]) continue;
				candidates.insert({ subtree[it], it });
			}
			cur_sz++;
		}
		auto it = candidates.end(); it--;
		if (it->first >= v[1].first) {
			vector <int> ans(n, 0);
			esim.clear();
			for (int i = 0; i < n; i++) {
				used[i] = false;
			}
			int w = it->second;
			sz = v[1].first;
			used[par[w]] = true;
			dfs(w);
			for (auto& it : f) {
				ans[it] = v[0].second;
			}
			for (auto& it : esim) {
				ans[it] = v[1].second;
			}
          	for (auto& it : ans) {
              if (it == 0) it = v[2].second;
            }
			return ans;
		}
	}
	swap(v[0], v[1]);
	if (ch) {
		set <pair<int, int>> candidates;
		for (auto it : G[0]) {
			candidates.insert({ subtree[it], it });
		}
		vector <int> f = { 0 };
		int cur_sz = 1;
		while (cur_sz < v[0].first) {
			auto it = candidates.begin();
			int v = it->second;
			f.push_back(v);
			for (auto it : G[v]) {
				if (it == par[v]) continue;
				candidates.insert({ subtree[it], it });
			}
			cur_sz++;
		}
		auto it = candidates.end(); it--;
		if (it->first >= v[1].first) {
			vector <int> ans(n, 0);
			esim.clear();
			for (int i = 0; i < n; i++) {
				used[i] = false;
			}
			int w = it->second;
			sz = v[1].first;
			used[par[w]] = true;
			dfs(w);
			for (auto& it : f) {
				ans[it] = v[0].second;
			}
			for (auto& it : esim) {
				ans[it] = v[1].second;
			}
          	for (auto& it : ans) {
              if (it == 0) it = v[2].second;
            }
			return ans;
		}
	}
	vector <int> ans(n, 0);
	return ans; 
}
/*int main() {
}*/

Compilation message (stderr)

split.cpp: In function 'std::vector<int> find_split(int, int, int, int, std::vector<int>, std::vector<int>)':
split.cpp:48:15: warning: variable 'b' set but not used [-Wunused-but-set-variable]
   48 |   int a = -1, b = -1;
      |               ^

• Subtask 1: 7 / 7
• Subtask 2: 11 / 11
• Subtask 3: 0 / 22
• Subtask 4: 0 / 24
• Subtask 5: 0 / 36