Submission #991991

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Source Code Expand

#include <bits/stdc++.h>
using namespace std;
int rt(int *uf,int i)
{
  return uf[i]<0?i:uf[i]=rt(uf,uf[i]);
}

void con(int *uf,int a,int b)
{
  a=rt(uf,a);
  b=rt(uf,b);
  if(a!=b){
    if(-uf[a]<-uf[b]){
      uf[a]=b;
    }
    else if(-uf[a]>-uf[b]){
      uf[b]=a;
    }
    else{
      uf[a]=b;
      uf[b]--;
    }
  }
}

int main()
{
  int n,m;
  scanf("%d%d",&n,&m);
  static int uf[200000];
  for(int i=0;i<n+m;i++){
    uf[i]=-1;
  }
  for(int i=0;i<n;i++){
    int K;
    scanf("%d",&K);
    while(K--){
      int l;
      scanf("%d",&l);
      l--;
      con(uf,i,n+l);
    }
  }
  int R=rt(uf,0);
  bool F=0;
  for(int i=1;i<n;i++){
    int r=rt(uf,i);
    if(r!=R){
      F=1;
    }
  }
  puts(!F?"YES":"NO");
  return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:29:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d",&n,&m);
                      ^
./Main.cpp:36:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&K);
                   ^
./Main.cpp:39:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
       scanf("%d",&l);
                     ^

Judge Result