Submission #1049950

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
1049950	2024-08-09T06:18:26 Z	mychecksedad	Connecting Supertrees (IOI20_supertrees)	C++17	19 / 100	121 ms	28148 KB

supertrees

#include "supertrees.h"
#include<bits/stdc++.h>
using namespace std;
#define ll long long int
#define pb push_back
#define vi vector<int>
 

struct Dsu{
	vector<int> p, s;
	Dsu(int n){
		p.resize(n+1);
		s.resize(n+1,1);
		for(int i = 1; i <= n; ++i ) p[i]=i;
	}
	int find(int v){
		if(p[v] == v)return v;
		return p[v]=find(p[v]);
	}
	void merge(int a, int b){
		a = find(a);
		b = find(b);
		if(a != b){
			if(s[a]>s[b]) swap(a,b);
			p[a] = b;
			s[b] += s[a];
		}
	}
};
vector<vector<int>> P;
bool solve(vector<int> v, vector<vector<int>> &ans){
	if(v.empty()) return 1;
	for(int u: v){
		for(int x: v){
			if(P[u][x] == 0 || P[u][x] == 3){
				return 0;
			}
		}
	}
	vector<int> cycle;
	vector<vector<int>> onepiece;
	vector<bool> used(v.size());
	for(int i = 0; i < v.size(); ++i){
		bool fulltwo = 1;
		for(int j = i + 1; j < v.size(); ++j){
			if(P[v[i]][v[j]] == 1){
				fulltwo = 0;
				onepiece.pb(vector<int>{v[i], v[j]});
				used[i] = used[j] = 1;
				for(int k = j + 1; k < v.size(); ++k){	
					if(!used[k]){
						int co = 0;
						for(int c: onepiece.back()){
							if(P[c][v[k]] == 1){
								++co;
							}
						}
						if(co != 0 && co != onepiece.back().size()){
							return 0;
						}
						if(co == onepiece.back().size()){
							onepiece.back().pb(v[k]);
							used[k] = 1;
						}
					}
				}
			}
		}
		if(fulltwo) cycle.pb(v[i]);
		// else assert(false);
	}

	if(v.size() == 2 && cycle.size() == 2) return 0;

	for(auto x: onepiece){
		for(int j = 0; j + 1 < x.size(); ++j){
			ans[x[j]][x[j + 1]] = ans[x[j + 1]][x[j]] = 1;
		}
		cycle.pb(x[0]);
	}
	if(cycle.size() == 1 && v.size() == 1) return 1;
	if(cycle.size() == 1) return 0;
	for(int i = 0; i < cycle.size(); ++i){
		ans[cycle[i]][cycle[(i + 1) % cycle.size()]] = ans[cycle[(i + 1) % cycle.size()]][cycle[i]] = 1;
	}

	return 1;
}

int construct(std::vector<std::vector<int>> p) {
	int n = p.size();
	P = p;
	vector<vector<int>> answer(n, vector<int>(n));

	Dsu d(n);

	for(int i = 0; i < n; ++i){
		for(int j = 1; j < n; ++j){
			if(p[i][j] > 0) d.merge(i, j);
		}
	}

	vector<vector<int>> C(n);
	for(int i = 0; i < n; ++i){
		C[d.find(i)].pb(i);
	}
	for(auto v: C){
		bool ok = solve(v, answer);
		if(!ok) return 0;
	}


	build(answer);
	return 1;
}

Compilation message

supertrees.cpp: In function 'bool solve(std::vector<int>, std::vector<std::vector<int> >&)':
supertrees.cpp:43:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |  for(int i = 0; i < v.size(); ++i){
      |                 ~~^~~~~~~~~~
supertrees.cpp:45:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   45 |   for(int j = i + 1; j < v.size(); ++j){
      |                      ~~^~~~~~~~~~
supertrees.cpp:50:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   50 |     for(int k = j + 1; k < v.size(); ++k){
      |                        ~~^~~~~~~~~~
supertrees.cpp:58:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   58 |       if(co != 0 && co != onepiece.back().size()){
      |                     ~~~^~~~~~~~~~~~~~~~~~~~~~~~~
supertrees.cpp:61:13: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   61 |       if(co == onepiece.back().size()){
      |          ~~~^~~~~~~~~~~~~~~~~~~~~~~~~
supertrees.cpp:76:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   76 |   for(int j = 0; j + 1 < x.size(); ++j){
      |                  ~~~~~~^~~~~~~~~~
supertrees.cpp:83:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   83 |  for(int i = 0; i < cycle.size(); ++i){
      |                 ~~^~~~~~~~~~~~~~

Subtask #1
0 / 11.0

#	Verdict	Memory	Grader output
1	Correct	344 KB	Output is correct
2	Correct	348 KB	Output is correct
3	Incorrect	348 KB	b[0][0] is not 0
4	Halted	0 KB	-

Subtask #2
0 / 10.0

#	Verdict	Memory	Grader output
1	Correct	344 KB	Output is correct
2	Correct	348 KB	Output is correct
3	Incorrect	348 KB	b[0][0] is not 0
4	Halted	0 KB	-

Subtask #3
19.0 / 19.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	348 KB	Output is correct
2	Correct	0 ms	348 KB	Output is correct
3	Correct	0 ms	348 KB	Output is correct
4	Correct	0 ms	348 KB	Output is correct
5	Correct	0 ms	348 KB	Output is correct
6	Correct	0 ms	348 KB	Output is correct
7	Correct	0 ms	348 KB	Output is correct
8	Correct	4 ms	1372 KB	Output is correct
9	Correct	121 ms	27880 KB	Output is correct
10	Correct	1 ms	348 KB	Output is correct
11	Correct	0 ms	348 KB	Output is correct
12	Correct	5 ms	1372 KB	Output is correct
13	Correct	100 ms	27988 KB	Output is correct
14	Correct	1 ms	344 KB	Output is correct
15	Correct	1 ms	348 KB	Output is correct
16	Correct	4 ms	1116 KB	Output is correct
17	Correct	72 ms	18088 KB	Output is correct
18	Correct	0 ms	348 KB	Output is correct
19	Correct	0 ms	348 KB	Output is correct
20	Correct	0 ms	348 KB	Output is correct
21	Correct	26 ms	7188 KB	Output is correct
22	Correct	98 ms	28044 KB	Output is correct
23	Correct	104 ms	27908 KB	Output is correct
24	Correct	105 ms	27984 KB	Output is correct
25	Correct	43 ms	18184 KB	Output is correct
26	Correct	49 ms	18188 KB	Output is correct
27	Correct	99 ms	27924 KB	Output is correct
28	Correct	110 ms	28148 KB	Output is correct
29	Correct	42 ms	18000 KB	Output is correct