Submission #472894

#	Time	Username	Problem	Language	Result	Execution time	Memory
472894		aris12345678	슈퍼트리 잇기 (IOI20_supertrees)	C++14	Compilation error	0 ms	0 KiB

supertrees

#include "supertrees.h"
#include <bits/stdc++.h>
using namespace std;

const int mxN = 1005;
int par[mxN], siz[mxN];
vector<int> adj[mxN];
bool vis[mxN];
/*
void build(vector<vector<int> > b) {
    int n = int(b.size());
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < n; j++)
            cout << b[i][j] << " ";
        cout << "\n";
    }
}
*/
void make_set(int x) {
    par[x] = x, siz[x] = 1;
}

int find_set(int x) {
    return x == par[x] ? x : par[x] = find_set(par[x]);
}

void union_sets(int a, int b) {
    a = find_set(a), b = find_set(b);
    if(a == b) return false;
    if(siz[a] < siz[b])
        swap(a, b);
    par[b] = a, siz[a] += siz[b];
    return true;
}

int construct(vector<vector<int> > p) {
    int n = int(p.size());
    for(int i = 0; i < n; i++)
        make_set(i);
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < n; j++) {
            if(p[i][j] == 2) {
                if(union_sets(i, j)) {
                    int parent = find_set(i);
                    if(parent == i)
                        adj[parent].push_back(j);
                    else if(parent == j)
                        adj[parent].push_back(i);
                    else {
                        adj[parent].push_back(i);
                        adj[parent].push_back(j);
                    }
                }
            }
        }
    }
    for(int i = 0; i < n; i++) {
        if(siz[find_set(i)] <= 2)
            return 0;
        for(int j = 0; j < n; j++) {
            if(p[i][j] == 0 && find_set(i) == find_set(j))
                return 0;
        }
    }
    vector<vector<int> > b(n, vector<int>(n, 0));
    for(int i = 0; i < n; i++) {
        int parent = find_set(i);
        if(parent == i) continue;
        b[i][parent] = b[parent][i] = 1;
        if(!vis[parent]) {
            b[adj[parent][0]][adj[parent][1]] = b[adj[parent][1]][adj[parent][0]] = 1;
            vis[parent] = true;
        }
    }
    build(b);
    return 1;
}
/*
int main() {
    int n;
    scanf("%d", &n);
    vector<vector<int> > p(n, vector<int>(n));
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < n; j++)
            scanf("%d", &p[i][j]);
    }
    cout << "\n";
    printf("%d\n", construct(p));
    return 0;
}
*/

Compilation message (stderr)

supertrees.cpp: In function 'void union_sets(int, int)':
supertrees.cpp:29:23: error: return-statement with a value, in function returning 'void' [-fpermissive]
   29 |     if(a == b) return false;
      |                       ^~~~~
supertrees.cpp:33:12: error: return-statement with a value, in function returning 'void' [-fpermissive]
   33 |     return true;
      |            ^~~~
supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:43:30: error: could not convert 'union_sets(i, j)' from 'void' to 'bool'
   43 |                 if(union_sets(i, j)) {
      |                    ~~~~~~~~~~^~~~~~
      |                              |
      |                              void