Submission #718786

#	Time	Username	Problem	Language	Result	Execution time	Memory
718786		mseebacher	Split the Attractions (IOI19_split)	C++17	22 / 100	496 ms	1048576 KiB

split

#include "split.h"
#include <bits/stdc++.h>
 
using namespace std;
 
 
#define MAX_N (int) 1e5+5
vector<int> ad[MAX_N];
vector<int> res;
vector<bool> vis(MAX_N,0);
vector<pair<int,int>> cnt;
vector<int> sz(MAX_N,0);
vector<int> max_child(MAX_N,0);
int node = -1;
int parent = -1;

void dfs_size(int x,int e){
	sz[x] = 1;
	max_child[x] = 0;
	for(auto s: ad[x]){
		if(s == e) continue;
		dfs_size(s,x);
		sz[x] += sz[s];
		max_child[x] = max(max_child[x],sz[s]);
	}
}

void dfs1(int x, int e){
	if(sz[x] < cnt[0].first) return;
	if(sz[x] >= cnt[0].first && sz[0] - sz[x] >= cnt[1].first){
		node = x;
		parent = e;
		return;
	}
	if(sz[x] >= cnt[1].first && sz[0] - sz[x] >= cnt[0].first){
		parent = x;
		node = e;
		return; 
	}
	for(auto s: ad[x]){
		if(s == e) continue;
		dfs1(s,x);
	}
}

void dfs2(int x,int e,int side){
	if(cnt[side].first == 0) return; 
	res[x] = cnt[side].second;
	cnt[side].first--;
	for(auto s: ad[x]){
		if(vis[s] || s == e) continue;
		dfs2(s,x,side);
	}
}
 
vector<int> find_split(int n, int a, int b, int c, vector<int> p, vector<int> q) {
	for(int i = 0;i<(int)p.size();i++){
		ad[p[i]].push_back(q[i]);
		ad[q[i]].push_back(p[i]);
	}
	res.assign(n,0);
	if(a >= n-1 || b >= n-1 || c>=n-1) return res;
	cnt.push_back({a,1});
	cnt.push_back({b,2});
	cnt.push_back({c,3});
	sort(cnt.begin(),cnt.end());
	res.assign(n,cnt[2].second);
	dfs_size(0,-1);
	dfs1(0,-1);
	if(node == -1) return vector<int>(n,0);
	vis[node] = vis[parent] = 1;
	dfs2(node,node,0);
	dfs2(parent,parent,1);
	return res;
}

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