Submission #829561

#	Time	Username	Problem	Language	Result	Execution time	Memory
829561		faruk	Connecting Supertrees (IOI20_supertrees)	C++17	21 / 100	181 ms	24084 KiB

supertrees

#include "supertrees.h"
#include <iostream>
#include <vector>
#include <algorithm>
#define mp make_pair
#define all(a) a.begin(), a.end()

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;

int n;
bool check_components(vector<vector<int> > p) {
	vector<int> comp(n, -1);
	for (int i = 0; i < n; i++) {
		if (p[i][i] != 1)
			return false;
		if (comp[i] == -1) {
			for (int j = 0; j < n; j++) {
				if (p[i][j] != 0 and comp[j] != -1)
					return false;
				if (p[i][j])
					comp[j] = i;
			}
		}
		else {
			for (int j = 0; j < n; j++)
				if (p[i][j] != 0 and comp[j] != comp[i])
					return false;
		}
	}
	return true;
}

int construct(std::vector<std::vector<int>> p) {
	n = p.size();
	std::vector<std::vector<int>> answer;
	if (check_components(p) == false)
		return 0;
	vector<bool> visited(n);
	vector<vector<int> > out(n, vector<int>(n, 0));
	for (int i = 0; i < n; i++) {
		if (visited[i])
			continue;
		vector<int> mine;
		for (int j = 0; j < n; j++)
			if (p[i][j] != 0)
				mine.push_back(j), visited[j] = true;
		if (mine.size() == 1)
			continue;

		vector<int> all2, everyone_else;
		for (int a : mine) {
			bool has1 = false;
			for (int j : mine)
				if (p[a][j] == 1 and j != a)
					has1 = true;
			if (has1)
				everyone_else.push_back(a);
			else
				all2.push_back(a);
		}
		for (int a : everyone_else) {
			for (int b : all2)
				if (p[a][b] != 2)
					return 0;
			for (int b : everyone_else)
				if (p[a][b] != 1)
					return 0;
		}

		if (everyone_else.size() == 0) { // cycle
			for (int i = 0; i < all2.size(); i++)
			{
				int f = all2[i], s = i < (all2.size() - 1) ? all2[i + 1] : all2[0];
				out[f][s] = 1, out[s][f] = 1;
			}
		}
		else if (all2.size() == 0) {// line
			for (int i = 0; i < everyone_else.size() - 1; i++)
			{
				int f = everyone_else[i], s = everyone_else[i + 1];
				out[f][s] = 1, out[s][f] = 1;
			}
		}
		else {
			// made cycle chain
			for (int i = 0; i < all2.size() - 1; i++)
			{
				int f = all2[i], s = all2[i + 1];
				out[f][s] = 1, out[s][f] = 1;
			}

			// made one chain
			for (int i = 0; i < everyone_else.size() - 1; i++)
			{
				int f = everyone_else[i], s = everyone_else[i + 1];
				out[f][s] = 1, out[s][f] = 1;
			}

			int A = everyone_else[0], B = all2[0], C = all2.back();
			out[A][B] = 1;
			out[B][A] = 1;
			out[A][C] = 1;
			out[C][A] = 1;
		}
	}
	build(out);
	return 1;
}

Compilation message (stderr)

supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:74:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   74 |    for (int i = 0; i < all2.size(); i++)
      |                    ~~^~~~~~~~~~~~~
supertrees.cpp:76:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   76 |     int f = all2[i], s = i < (all2.size() - 1) ? all2[i + 1] : all2[0];
      |                          ~~^~~~~~~~~~~~~~~~~~~
supertrees.cpp:81:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   81 |    for (int i = 0; i < everyone_else.size() - 1; i++)
      |                    ~~^~~~~~~~~~~~~~~~~~~~~~~~~~
supertrees.cpp:89:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   89 |    for (int i = 0; i < all2.size() - 1; i++)
      |                    ~~^~~~~~~~~~~~~~~~~
supertrees.cpp:96:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   96 |    for (int i = 0; i < everyone_else.size() - 1; i++)
      |                    ~~^~~~~~~~~~~~~~~~~~~~~~~~~~

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