Submission #949963

#	Time	Username	Problem	Language	Result	Execution time	Memory
949963		irmuun	Connecting Supertrees (IOI20_supertrees)	C++17	Compilation error	0 ms	0 KiB

supertrees

#include<bits/stdc++.h>
//#include "supertrees.h"

using namespace std;

#define ll long long
#define pb push_back
#define ff first
#define ss second
#define all(s) s.begin(),s.end()
#define rall(s) s.rbegin(),s.rend()

struct dsu{
    int n;
    vector<int>sz,par;
    dsu(int n):n(n){
        sz.resize(n);
        par.resize(n);
        fill(all(sz),1);
        iota(all(par),0);
    }
    int find(int x){
        if(par[x]==x) return x;
        return par[x]=find(par[x]);
    }
    void merge(int x,int y){
        x=find(x);
        y=find(y);
        if(x!=y){
            if(sz[x]<sz[y]){
                swap(x,y);
            }
            sz[x]+=sz[y];
            par[y]=x;
        }
    }
};

int construct(vector<vector<int>>p){
    int n=p.size();
    bool a[4];
    for(int i=0;i<n;i++){
        for(int j=0;j<n;j++){
            a[p[i][j]]=true;
        }
    }
    vector<vector<int>>b(n,vector<int>(n,0));
    if(!a[2]&&!a[3]){
        vector<bool>used(n,0);
        vector<int>ver;
        for(int i=0;i<n;i++){
            if(!used[i]){
                queue<int>q;
                q.push(i);
                used[i]=true;
                while(!q.empty()){
                    int x=q.front();
                    ver.pb(x);
                    q.pop();
                    for(int j=0;j<n;j++){
                        if(p[x][j]==1&&!used[j]){
                            used[j]=true;
                            q.push(j);
                        }
                    }
                }
                for(auto x:ver){
                    for(auto y:ver){
                        if(x!=y&&p[x][y]!=1){
                            return 0;
                        }
                    }
                }
                for(int j=1;j<ver.size();j++){
                    b[ver[j]][ver[j-1]]=1;
                    b[ver[j-1]][ver[j]]=1;
                }
                ver.clear();
            }
        }
        build(b);
        return 1;
    }
    if(a[0]&&!a[1]&&a[2]&&!a[3]){
        vector<bool>used(n,0);
        vector<int>ver;
        for(int i=0;i<n;i++){
            if(!used[i]){
                queue<int>q;
                q.push(i);
                used[i]=true;
                while(!q.empty()){
                    int x=q.front();
                    ver.pb(x);
                    q.pop();
                    for(int j=0;j<n;j++){
                        if(p[x][j]==2&&!used[j]){
                            used[j]=true;
                            q.push(j);
                        }
                    }
                }
                for(auto x:ver){
                    for(auto y:ver){
                        if(x!=y&&p[x][y]!=2){
                            return 0;
                        }
                    }
                }
                for(int j=1;j<ver.size();j++){
                    b[ver[j]][ver[j-1]]=1;
                    b[ver[j-1]][ver[j]]=1;
                }
                if(ver.size()>1){
                    b[ver[0]][ver.back()]=1;
                    b[ver.back()][ver[0]]=1;
                }
                ver.clear();
            }
        }
        build(b);
        return 1;
    }
    return 0;
}

Compilation message (stderr)

supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:74:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   74 |                 for(int j=1;j<ver.size();j++){
      |                             ~^~~~~~~~~~~
supertrees.cpp:81:9: error: 'build' was not declared in this scope
   81 |         build(b);
      |         ^~~~~
supertrees.cpp:110:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  110 |                 for(int j=1;j<ver.size();j++){
      |                             ~^~~~~~~~~~~
supertrees.cpp:121:9: error: 'build' was not declared in this scope
  121 |         build(b);
      |         ^~~~~