Submission #306537

#	Time	Username	Problem	Language	Result	Execution time	Memory
306537		vivaan_gupta	Connecting Supertrees (IOI20_supertrees)	C++14	11 / 100	249 ms	22264 KiB

supertrees

#include <algorithm>
#include <bitset>
#include <cassert>
#include <chrono>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <limits>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <ratio>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
#include <climits>
#include "supertrees.h"
#define ll long long
#define ld long double
#define mp make_pair
#define pb push_back
#define in insert
#define vll vector<ll>
#define endl "\n"
#define f first
#define s second
// #define int ll
using namespace std;

 


 
struct DSU
{
	int connected;
	vector<int> par, sz;

	void init(int n) 
	{
		par = sz = vector<int> (n + 1, 0);
		for(int i = 1; i <= n; i++)
			par[i] = i, sz[i] = 1;
		connected = n;
	}

	int getPar(int u)
	{
		while(u != par[u])
		{
			par[u] = par[par[u]];
			u = par[u];
		}
		return u;
	}

	int getSize(int u)
	{
		return sz[getPar(u)];
	}

	void unite(int u, int v)
	{
		int par1 = getPar(u), par2 = getPar(v);

		if(par1 == par2)
			return;

		connected--;

		if(sz[par1] > sz[par2])
			swap(par1, par2);

		sz[par2] += sz[par1];
		sz[par1] = 0;
		par[par1] = par[par2];
	}
};



int construct(std::vector<std::vector<int>> p) {
	DSU g;
	int n = p.size();
	g.init(n-1);
	std::vector<std::vector<int>> ans;
	for (int i = 0; i < n; i++) {
		std::vector<int> row;
		row.resize(n);
		ans.push_back(row);
	}
	bool ok = false;
	bool ok2 = false;
	for(int i = 0;i<n;i++){
		for(int j = 0;j<n;j++){
			ok |= (p[i][j] == 1);
			ok2 |= (p[i][j] == 2);
		}
	}

	if(!ok2 && !ok){
		for(int i =0;i<n;i++){
			for(int j =0;j<n;j++){
				ans[i][j] =0;
			}
		}
		build(ans);
		return 1;
	}

	if(!ok){
		for(int i =0;i<n;i++){
			for(int j =i+1;j<n;j++){
				if(p[i][j] == 2){
					g.unite(i,j);
				}
			}
		}
		map<int,int> col;
		vector<int> wow[n+1];
		int c = 1;
		for(int i =0;i<n;i++){
			int op = g.getPar(i);
			if(col[op] == 0){
				col[op] = c;
				c++;				
			}
			wow[col[op]].pb(i);
		}
		c--;
		for(int i =0;i<n;i++){
			for(int j =0;j<n;j++){
				ans[i][j] = 0;
			}
		}
		for(int i =1;i<=c;i++){
			if(wow[i].size() == 1) continue;
			for(int j= 0;j<wow[i].size()-1;j++){
				ans[wow[i][j]][wow[i][j+1]] = 1;
				ans[wow[i][j+1]][wow[i][j]] = 1;
			}
			ans[wow[i].back()][wow[i][0]] = 1;
			ans[wow[i][0]][wow[i].back()] = 1;
		}
		build(ans);
		return 1;
	}
	for(int i =0;i<n;i++){
		for(int j =i+1;j<n;j++){
			if(p[i][j] > 0){
				g.unite(i,j);
			}
		}
	}
	map<int,int> col;
	vector<int> wow[n+1];
	int c = 1;
	for(int i =0;i<n;i++){
		int op = g.getPar(i);
		if(col[op] == 0){
			col[op] = c;
			c++;				
		}
		wow[col[op]].pb(i);
	}
	c--;
	for(int i =0;i<n;i++){
		for(int j =0;j<n;j++){
			ans[i][j] = 0;
		}
	}
	for(int i =1;i<=c;i++){
		int sz = wow[i].size();
		ok = false;
		int cnt = 0;
		int idx = -1,idx2 = -1;
		int x = -1,y = -1;
		for(int j =0;j<sz;j++){
			for(int k = j+1;k<sz;k++){
				if(p[wow[i][j]][wow[i][k]] == 2){
					ok = true;
				}
				else if(p[wow[i][j]][wow[i][k]] == 1) {
					cnt++;
					idx = wow[i][j];
					idx2 = wow[i][k];
					x = j;
					y = k;
				}
			}
		}
		if(!ok){
			for(int j =0;j<sz-1;j++){
				ans[wow[i][j]][wow[i][j+1]] = 1;
				ans[wow[i][j+1]][wow[i][j]] = 1;
			}
			continue;
		}
		if(idx == -1){
			for(int j = 0;j<sz-1;j++){
				ans[wow[i][j]][wow[i][j+1]] = 1;
				ans[wow[i][j+1]][wow[i][j]] = 1;
			}
			ans[wow[i].back()][wow[i][0]] = 1;
			ans[wow[i][0]][wow[i].back()] = 1;
			continue;
		}
		// assert(cnt == 1);
		ans[idx][idx2] = 1;
		ans[idx2][idx] = 1;
		vector<int> v;
		for(int j = 0;j<sz;j++){
			if(j != x){
				v.pb(wow[i][j]);
			}
		}
		for(int j = 0;j<v.size()-1;j++){
			ans[v[j]][v[j+1]] = 1;
			ans[v[j+1]][v[j]] = 1;
		}
		ans[v.back()][v[0]] = 1;
		ans[v[0]][v.back()] = 1;		
	}
	build(ans);
	return 1;
}


// void solve(){
	
// }
// signed main(){
 
//     ios_base::sync_with_stdio(0);
//     cin.tie(NULL);
//      // freopen(".in","r",stdin);freopen(".out","w",stdout);
    
//      ll tt=1;   
//      // cin >> tt;
//     while(tt--){    
//         solve();
//     }    
// }

Compilation message (stderr)

supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:152:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  152 |    for(int j= 0;j<wow[i].size()-1;j++){
      |                 ~^~~~~~~~~~~~~~~~
supertrees.cpp:231:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  231 |   for(int j = 0;j<v.size()-1;j++){
      |                 ~^~~~~~~~~~~
supertrees.cpp:191:14: warning: variable 'y' set but not used [-Wunused-but-set-variable]
  191 |   int x = -1,y = -1;
      |              ^

• Subtask 1: 11 / 11
• Subtask 2: 0 / 10
• Subtask 3: 0 / 19
• Subtask 4: 0 / 35
• Subtask 5: 0 / 21
• Subtask 6: 0 / 4