Submission #433580

#	Time	Username	Problem	Language	Result	Execution time	Memory
433580		sean617	Connecting Supertrees (IOI20_supertrees)	C++17	100 / 100	302 ms	23176 KiB

supertrees

#include "supertrees.h"
#include <vector>
#include <cstring>
#define N 1005

using namespace std;
int n, cnt, bu[N], bu2[N], gut[N];
bool v[N], co[N][N], icy[N];
vector<int> gu[N], cy[N], cy2, ans, ch[N];
vector<std::vector<int> > answer;
int f(int p) {
    if (bu[p] == p) return p;
    else return bu[p] = f(bu[p]);
}

int f2(int p) {
	if (bu2[p] == p) return p;
	else return bu2[p] = f2(bu2[p]);
}

void f_co(int p, int q) {
    co[p][q] = co[q][p] = 1;
}

int construct(std::vector<std::vector<int> > p) {
    int i, j, k, t, t1, t2, la, tcnt;
	n = p.size();
	for (i = 0; i < n; i++) {bu[i] = i; bu2[i] = i;}
	for (i = 0; i < n; i++) {
        for (j = i + 1; j < n; j++) {
            if (p[i][j]== 0) continue;
            if (p[i][j] == 3) return 0;
            t1 = f(i);
            t2 = f(j);
            if (t1 != t2) bu[t1] = t2;
        }
	}
	memset(gut, -1, sizeof(gut));
	for (i = 0; i < n; i++) f(i);
	for (i = 0; i < n; i++) {
		tcnt = 0;
		for (j = 0; j < n; j++) {
			if (i == j) continue;
			if (bu[i] != bu[j]) continue;
			if (p[i][j] == 0) return 0;
			if (p[i][j] == 1) {
				t1 = f2(i);
				t2 = f2(j);
				if (t1 != t2) bu2[t1] = t2;
				tcnt++;
			}
		}
		if (tcnt == 0) {
			icy[i] = 1;
			cy[bu[i]].push_back(i);
		}
	}
	for (i = 0; i < n; i++) {
		for (j = i + 1; j < n; j++) {
			if (bu2[i] != bu2[j]) continue;
			if (p[i][j] != 1) return 0;
		}
	}
	for (i = 0; i < n; i++) {
		if (cy[i].empty()) continue;
		for (j = 0; j < cy[i].size(); j++) {
			for (k = j + 1; k < cy[i].size(); k++) {
				t1 = cy[i][j];
				t2 = cy[i][k];
				if (p[t1][t2] != 2) return 0;
			}
		}
	}
	for (i = 0; i < n; i++) {
		if (icy[i]) continue;
		for (j = i + 1; j < n; j++) {
			if (bu[i] != bu[j]) continue;
			if (bu2[i] == bu2[j] && p[i][j] != 1 || bu2[i] != bu2[j] && p[i][j] != 2) return 0;
		}
		if (gut[bu2[i]] == -1) {
			cy[bu[i]].push_back(i);
		} else {
			f_co(gut[bu2[i]], i);
		}
		gut[bu2[i]] = i;
	}
	for (i = 0; i < n; i++) {
		if (cy[i].empty() || cy[i].size() == 1) continue;
		if (cy[i].size() == 2) return 0;
		int cysz = cy[i].size();
		for (j = 0; j < cysz; j++) {
			t1 = cy[i][j];
			t2 = cy[i][(j + 1) % cysz];
			f_co(t1, t2);
		}
	}
  for (i = 0; i < n; i++) {
        ans.clear();
        for (j =0; j < n; j++) {
            ans.push_back(co[i][j]);
        }
		answer.push_back(ans);
	}
	build(answer);
	return 1;
}

Compilation message (stderr)

supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:66:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   66 |   for (j = 0; j < cy[i].size(); j++) {
      |               ~~^~~~~~~~~~~~~~
supertrees.cpp:67:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   67 |    for (k = j + 1; k < cy[i].size(); k++) {
      |                    ~~^~~~~~~~~~~~~~
supertrees.cpp:78:25: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   78 |    if (bu2[i] == bu2[j] && p[i][j] != 1 || bu2[i] != bu2[j] && p[i][j] != 2) return 0;
      |        ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~
supertrees.cpp:26:18: warning: unused variable 't' [-Wunused-variable]
   26 |     int i, j, k, t, t1, t2, la, tcnt;
      |                  ^
supertrees.cpp:26:29: warning: unused variable 'la' [-Wunused-variable]
   26 |     int i, j, k, t, t1, t2, la, tcnt;
      |                             ^~

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