Submission #738037

#	Time	Username	Problem	Language	Result	Execution time	Memory
738037		bobthebuilder	Connecting Supertrees (IOI20_supertrees)	C++17	100 / 100	277 ms	24124 KiB

supertrees

#include "supertrees.h"
#include<bits/stdc++.h>
using namespace std;
#define sz(x) (int)x.size()
#define REP(i,n) for(int i=0;i<n;i++)
#define REP1(i,n) for(int i=1;i<=n;i++)
#define pb push_back
#define lowb(x) (x&(-x))
#define ALL(_x) _x.begin(),_x.end()
#define pii pair<int,int>
#define f first
#define s second
#define SORT_UNIQUE(x) sort(ALL(x)),x.erase(unique(ALL(x)),x.end())
#define MNTO(x,y) x=min(x,y)
const int maxn=1e3+5;
namespace {
struct uf{
	int par[maxn];
	void init(int n){
		REP(i,n) par[i]=i;
	}
	int find(int u){
		if(par[u]==u) return u;
		return par[u]=find(par[u]);
	}
	void merge(int a,int b){
		a=find(a),b=find(b);
		if(a==b) return;
		par[a]=b;
	}
}a,b;

vector<int> cmp[maxn],ln[maxn];
}
int construct(std::vector<std::vector<int>> p) {
	int n = p.size();
	vector<vector<int>> ans(n,vector<int>(n));
	REP(i,n){
		REP(j,n){
			if(p[i][j]==3){
				return 0;
			}
		}
		if(p[i][i]!=1){
			return 0;
		}
	}
	a.init(n),b.init(n);
	REP(i,n){
		REP(j,n){
			if(p[i][j]){
				a.merge(i,j);
			}
		}
	}
	REP(i,n){
		cmp[a.find(i)].pb(i);
	}
	REP(i,n){
		if(!sz(cmp[i])) continue;
		for(int x:cmp[i]){
			for(int y:cmp[i]){
				if(p[x][y]==0){
					return 0;
				}
				if(p[x][y]==1){
					b.merge(x,y);
				}
			}
		}
		for(int x:cmp[i]){
			for(int y:cmp[i]){
				if(p[x][y]==2 and b.find(x)==b.find(y)){
					return 0;
				}
			}
		}
		vector<int> cyc;
		for(int x:cmp[i]){
			cyc.pb(b.find(x));
			ln[b.find(x)].pb(x);
		}
		SORT_UNIQUE(cyc);
		if(sz(cyc)==2){
			return 0;
		}
		if(sz(cyc)>1){
			int k=sz(cyc);
			REP(j,k){
				ans[cyc[j]][cyc[(j+1)%k]]=ans[cyc[(j+1)%k]][cyc[j]]=1;
			}
		}
		for(int x:cmp[i]){
			for(int a:ln[x]){
				for(int b:ln[x]){
					if(p[a][b]!=1){
						return 0;
					}
				}
			}
			int pv=-1;
			for(int y:ln[x]){
				if(pv!=-1) ans[pv][y]=ans[y][pv]=1; 
				pv=y;
			}
		}
	}
	build(ans);
	return 1;
}

• Subtask 1: 11 / 11
• Subtask 2: 10 / 10
• Subtask 3: 19 / 19
• Subtask 4: 35 / 35
• Subtask 5: 21 / 21
• Subtask 6: 4 / 4