Submission #1212558

#	Time	Username	Problem	Language	Result	Execution time	Memory
1212558		loiiii12358	Split the Attractions (IOI19_split)	C++20	18 / 100	48 ms	14404 KiB

split

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

int N,node=-1;
pair<int,int> A,B,C;
vector<int> subtree,ans;
vector<vector<int>> edges;

void run(int u,int par,int tmp){
	if(tmp==1){
		if(A.first>0){
			ans[u]=A.second;
			A.first--;
		}else{
			return;
		}
	}else if(tmp==2){
		if(B.first>0){
			ans[u]=B.second;
			B.first--;
		}else{
			return;
		}
	}
	for(auto v:edges[u]){
		if(v!=par&&v!=node&&ans[v]==0){
			run(v,u,tmp);
		}
	}
}

void dfs(int u,int par){
	// cout << u << ' ' << par << '\n';
	for(auto v:edges[u]){
		if(v!=par){
			dfs(v,u);
			subtree[u]+=subtree[v];
			// cout << v << ' ' << subtree[v] << '\n';
			if(subtree[v]>=A.first&&N-subtree[v]>=B.first&&node==-1){
				node=v;
				run(v,u,1);
			}
		}
	}
}

vector<int> find_split(int n, int a, int b, int c, vector<int> p, vector<int> q) {
	int m=p.size();
	A={a,1};B={b,2};C={c,3};N=n;
	if(B<A){
		swap(A,B);
	}
	if(C<A){
		swap(A,C);
	}
	if(C<B){
		swap(B,C);
	}
	edges.resize(n);subtree.resize(n,1);ans.resize(n,0);
	for(int i=0;i<m;i++){
		edges[p[i]].push_back(q[i]);
		edges[q[i]].push_back(p[i]);
	}
	if(m==n-1){
		dfs(0,-1);
		if(node!=-1){
			run(0,-1,2);
			for(int i=0;i<n;i++){
				if(ans[i]==0){
					ans[i]=C.second;
				}
			}
		}
	}else{
		run(0,-1,1);
		for(int i=0;i<n;i++){
			if(ans[i]==0){
				run(i,-1,2);
				break;
			}
		}
		for(int i=0;i<n;i++){
			if(ans[i]==0){
				ans[i]=C.second;
			}
		}
	}
	return ans;
}

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