Submission #247172

#	Time	Username	Problem	Language	Result	Execution time	Memory
247172		errorgorn	Lokahian Relics (FXCUP4_lokahia)	C++17	100 / 100	6 ms	896 KiB

lokahia

#include <bits/stdc++.h>
#include "lokahia.h"
using namespace std;
 
#define ll long long
#define fi first
#define se second 

#define rep(x,s,e) for (auto x=s-(s>e);x!=e-(s>e);(s<e?x++:x--))
#define all(x) (x).begin(),(x).end()
#define sz(x) (int)(x).size()
mt19937 rng (177013);

const int trial=10; //test different startings
const int samples=7; //test different random places
const int pass=4;

int counter=0;

int memo[205][205];
int get(int i,int j){
	if (memo[i][j]!=-1) return memo[i][j];
	
	counter++;
	if (counter>=300) return -1; //scam.jpg
	
	return memo[i][j]=memo[j][i]=CollectRelics(i,j);
}


vector<int> shuf(vector<int> v){
	rep(x,0,sz(v)){
		swap(v[x],v[rng()%(x+1)]);
	}
	
	return v;
}

bool vis[205];

int FindBase(int n){
	memset(memo,-1,sizeof(memo));
	
	if (n<=20){ //maybe
		rep(root,0,n){
			int cnt=1;
			int ans=0;
			rep(x,0,n) if (x!=root){
				int temp=get(root,x);
		
				if (temp!=-1) cnt++,ans=max(ans,temp);
			}
			
			if (cnt>n/2) return ans;
		}
		
		return -1;
	}
	
	vector<int> v;
	rep(x,0,n) v.push_back(x);
	
	v=shuf(v);
	
	vector<int> cand;
	
	rep(x,0,trial){
		int node=v[x];
		int curr=0;
		rep(zzz,0,samples){
			int temp;
			
			do{
				temp=rng()%n;
			} while (temp==node);
			
			//cout<<"debug: "<<node<<" "<<temp<<endl;
			if (get(node,temp)!=-1) curr++;
			
		}
		
		if (curr>=pass){
			cand.push_back(node);
		}
	}
	
	for (auto &it:cand){
		if (vis[it]) continue;
		vis[it]=true;
		
		int cnt=1;
		int ans=-1;
		
		rep(x,0,n) if (!vis[x]){
			int temp=get(it,x);
			
			if (temp!=-1){
				ans=max(ans,temp);
				cnt++;
				vis[x]=true;
			}
		}
		
		//cout<<it<<" "<<cnt<<" "<<ans<<endl;
		
		if (cnt>n/2) return ans;
	}
	
	
	return -1;
}

• Subtask 1: 100 / 100