Submission #1076816

#	Time	Username	Problem	Language	Result	Execution time	Memory
1076816		Hectorungo_18	Connecting Supertrees (IOI20_supertrees)	C++14	100 / 100	138 ms	22100 KiB

supertrees

#include "supertrees.h"
#include <vector>
#include<bits/stdc++.h>
 
using namespace std;
 
 
 
const int N = 1e3+7;
int p[N];
int sz[N];
 
 
int pa(int u){
	p[u]=(p[u] == u ? u : pa(p[u]));
	return p[u];
}
 
bool sm(int u, int v){
	return pa(u) == pa(v);
}
 
void un(int u, int v){
	if(sm(u, v)) return;
	u = pa(u);
	v = pa(v);
	if(sz[v] > sz[u]) swap(u, v);
	sz[u]+=sz[v];
	p[v]=u;
}
 
int construct(vector<vector<int>> v) {
	int n = v.size();
	for(int i = 0; i <= n; i++){
		p[i]=i;
		sz[i]=1;
	}
	for(int i = 0; i < n; i++){
        bool ch = 0;
        if(pa(i)==i) ch = 1;
		for(int j = i+1; j < n; j++){
          if(v[i][j] == 3) return 0;
			if(ch){
                if(v[i][j] == 0) continue;
                if(pa(j) == j){
                    un(i, j);
                }
                else return 0;
			}
            else{
                if(v[i][j] == 0){
                  if(pa(i) == pa(j)) return 0;
                }
              else if(pa(i) != pa(j)) return 0;
              	
            }
		}
	}
 
    map<int, int> m;
    for(int i = 0; i < n; i++){
        vector<int> a(4, 0);
        for(int j = 0; j < n; j++){
            if(i == j) continue;
            a[v[i][j]]++;
        }
        if(a[1] > 0) m[i]=1;
        else if(a[2] > 0) m[i]=2;
        else if(a[3] > 0) m[i]=3;
        else m[i]=0;
    }
 
    vector<vector<int>> ans(n, vector<int> (n, 0));
    vector<int> sp(n);
    for(int i = 0; i < n; i++){
        sp[i]=pa(i);
    }
    for(int i = 0; i < n; i++){
        p[i]=i;
        sz[i]=i;
    }
    for(int i = 0; i < n; i++){
        if(sp[i] != i) continue;
        vector<int> w;
        for(int j = 0; j < n; j++){
            if(sp[j] == i) w.push_back(j);
        }
        vector<int> dd;
        for(int j = 0; j < w.size(); j++){
            int r = w[j];
 
            for(int k = 0; k < n; k++){
                if(k == r) continue;
                if(v[r][k] != 1) continue;
                if(pa(r) == pa(k)) continue;
                if(pa(r) == r){
                    un(r, k);
                }
                else{
                    if(pa(k) == k){
                        un(r, k);
                    }
                    else return 0;
                }
            }
        }
        for(int j = 0; j < w.size(); j++){
            if(w[j] == pa(w[j])) dd.push_back(w[j]);
        }
        if(dd.size() == 2) return 0;
        for(int j = 1; j < dd.size(); j++){
            ans[dd[j]][dd[j-1]] = 1;
            ans[dd[j-1]][dd[j]] = 1;
        }
        if(dd.size() > 2){
            ans[dd[0]][dd.back()] = 1;
            ans[dd.back()][dd[0]] = 1;
        }
        vector<vector<int>> adj(n);
        for(int i = 0; i < w.size(); i++){
            int r = w[i];
            adj[pa(r)].push_back(r);
        }
        for(int i = 0; i < n; i++){
            for(int j = 1; j < adj[i].size(); j++){
                ans[adj[i][j]][adj[i][j-1]] = 1;
                ans[adj[i][j-1]][adj[i][j]] = 1;
            }
        }
    }
    
    build(ans);
 
	return 1;
}

Compilation message (stderr)

supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:89:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   89 |         for(int j = 0; j < w.size(); j++){
      |                        ~~^~~~~~~~~~
supertrees.cpp:107:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  107 |         for(int j = 0; j < w.size(); j++){
      |                        ~~^~~~~~~~~~
supertrees.cpp:111:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  111 |         for(int j = 1; j < dd.size(); j++){
      |                        ~~^~~~~~~~~~~
supertrees.cpp:120:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  120 |         for(int i = 0; i < w.size(); i++){
      |                        ~~^~~~~~~~~~
supertrees.cpp:125:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  125 |             for(int j = 1; j < adj[i].size(); j++){
      |                            ~~^~~~~~~~~~~~~~~

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