#include "supertrees.h"
#include <bits/stdc++.h>
using namespace std;
const int N = 1e3;
int par[N + 5], sz[N + 5];
vector<int> ls[N + 5];
int vertex[N + 5];
bool vis[N + 5];
int find(int x) { return x == par[x] ? x : find(par[x]); }
bool same(int x, int y) { return find(x) == find(y); }
void unite(int x, int y) {
x = find(x), y = find(y);
if (sz[x] < sz[y]) swap(x, y);
sz[x] += sz[y], par[y] = x;
}
int construct(std::vector<std::vector<int>> p) {
int n = p.size();
// check connectivity
for (int i = 0; i < n; i++) par[i] = i, sz[i] = 1;
for (int i = 0; i < n; i++) {
for (int j = i + 1; j < n; j++) {
if (p[i][j] && !same(i, j)) unite(i, j);
}
}
for (int i = 0; i < n; i++) {
for (int j = i + 1; j < n; j++) {
if (!p[i][j] && same(i, j)) return 0;
}
}
for (int i = 0; i < n; i++) ls[find(i)].push_back(i);
for (int i = 0; i < n; i++) vertex[i] = -1;
vector<vector<int>> b(n, vector<int>(n));
for (auto&arr : ls) {
if (arr.empty()) continue;
int sz = arr.size(), hasTwo = false, hasThree = false;
for (int i = 0; i < sz; i++){
for (int j = i + 1; j < sz; j++) {
int u = arr[i], v = arr[j];
hasTwo |= p[u][v] == 2, hasThree |= p[u][v] == 3;
}
}
if (hasTwo && hasThree) return 0;
if (!hasTwo && !hasThree) {
for (int i = 0; i + 1 < sz; i++){
int u = arr[i], v = arr[i + 1];
b[u][v] = b[v][u] = 1;
}
continue;
}
vector<int> loop;
for (int i = 0, flag = 0; !flag && i < sz; i++) {
for (int j = i + 1; j < sz; j++) {
int u = arr[i], v = arr[j];
if (p[u][v] >= 2) {
loop.push_back(u), loop.push_back(v);
vertex[u] = -1, vertex[v] = -1;
flag = true;
break;
}
}
}
for (int i = 0; i < sz; i++) {
int valid = 1, u = arr[i];
for (auto&v : loop) valid &= u != v && p[u][v] >= 2;
if (valid) loop.push_back(u);
}
/*cout << "LOOP" << '\n';
for (auto&v : loop) cout << v << " ";
cout << '\n';*/
if (hasTwo && loop.size() <= 2) return 0;
else if (hasThree && loop.size() <= 3) return 0;
for (int i = 0; i < loop.size(); i++) {
int u = loop[i], v = loop[(i + 1) % loop.size()];
b[u][v] = b[v][u] = 1;
}
if (hasThree) b[loop[0]][loop[2]] = b[loop[2]][loop[0]] = 1;
queue<int> q;
for (auto&v : loop) q.push(v), vis[v] = true;
while (q.size()) {
int u = q.front(); q.pop();
for (int i = 0; i < sz; i++) {
int v = arr[i];
if (v == u || vis[v] || p[v][u] != 1) continue;
vis[v] = true;
if (vertex[u] == -1) vertex[v] = u;
else vertex[v] = vertex[u];
q.push(v);
b[u][v] = b[v][u] = 1;
}
}
for (int i = 0; i < sz; i++) {
for (int j = i + 1; j < sz; j++) {
int u = arr[i], v = arr[j];
if (vertex[u] != -1 && vertex[v] != -1 && p[u][v] >= 2 && vertex[u] != vertex[v]) return 0;
}
}
}
build(b);
return 1;
}
static int n;
static std::vector<std::vector<int>> p;
static std::vector<std::vector<int>> b;
static bool called = false;
static void check(bool cond, std::string message) {
if (!cond) {
printf("%s\n", message.c_str());
fclose(stdout);
exit(0);
}
}
void build(std::vector<std::vector<int>> _b) {
check(!called, "build is called more than once");
called = true;
check((int)_b.size() == n, "Invalid number of rows in b");
for (int i = 0; i < n; i++) {
check((int)_b[i].size() == n, "Invalid number of columns in b");
}
b = _b;
}
int main() {
//assert(scanf("%d", &n) == 1);
cin >> n;
p.resize(n);
for (int i = 0; i < n; i++) {
p[i].resize(n);
}
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
//assert(scanf("%d", &p[i][j]) == 1);
cin >> p[i][j];
}
}
//fclose(stdin);
int possible = construct(p);
check(possible == 0 || possible == 1, "Invalid return value of construct");
if (possible == 1) {
check(called, "construct returned 1 without calling build");
} else {
check(!called, "construct called build but returned 0");
}
printf("%d\n", possible);
if (possible == 1) {
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
if (j) {
printf(" ");
}
printf("%d", b[i][j]);
}
printf("\n");
}
}
// fclose(stdout);
}
Compilation message
supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:82:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
82 | for (int i = 0; i < loop.size(); i++) {
| ~~^~~~~~~~~~~~~
/usr/bin/ld: /tmp/ccNfbV9h.o: in function `build(std::vector<std::vector<int, std::allocator<int> >, std::allocator<std::vector<int, std::allocator<int> > > >)':
grader.cpp:(.text+0x320): multiple definition of `build(std::vector<std::vector<int, std::allocator<int> >, std::allocator<std::vector<int, std::allocator<int> > > >)'; /tmp/cchDtr9i.o:supertrees.cpp:(.text+0x360): first defined here
/usr/bin/ld: /tmp/ccNfbV9h.o: in function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/cchDtr9i.o:supertrees.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status
