Submission #1831940

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Source Code Expand

# include <bits/stdc++.h>

# define pb push_back
# define fr first
# define sc second
# define mk make_pair

using namespace std;

const int inf = 1e9 + 7;
const int N = 1e5 + 5;

typedef long long ll;

int n, m, u[N], u1[N];
vector <int> g[N], a[N];

void dfs(int v, int type)
{
      if(type)
      {
            u1[v] = 1;
            for(int to : g[v])
            {
                  if(u[to]) continue;
                  dfs(to, 1 - type);
            }
      }
      else
      {
            u[v] = 1;
            for(int to : a[v])
            {
                  if(u1[to]) continue;
                  dfs(to, 1 - type);
            }
      }
}

int main()
{
      cin >> n >> m;

      for(int i = 1; i <= n; i ++)
      {
            int k, x;
            scanf("%d", &k);
            for(int j = 1; j <= k; j ++)
            {
                  scanf("%d", &x);
                  g[i].pb(x);
                  a[x].pb(i);
            }
      }

      int cnt = 0;

      for(int i = 1; i <= n; i ++)
            if(!u1[i])
            {
                  cnt ++;
                  dfs(i, 1);
            }

      if(cnt == 1)
            cout << "YES" << endl;
      else
            cout << "NO" << endl;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:47:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d", &k);
                            ^
./Main.cpp:50:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
                   scanf("%d", &x);
                                  ^

Judge Result