/in/foo.cc: In function 'void dfs(int, int)':
/in/foo.cc:11:17: error: 'f' was not declared in this scope
   11 |         int num=f[u]+cnt;
      |                 ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:19:9: error: 'i' was not declared in this scope
   19 |     for(i=2;i<=n;i++)
      |         ^
/in/foo.cc:25:9: error: 'i' was not declared in this scope
   25 |     for(i=1;i<=n;i++)
      |         ^
/in/foo.cc:28:9: error: 'f' was not declared in this scope
   28 |         f[x]++;
      |         ^
/in/foo.cc:31:13: error: 'i' was not declared in this scope
   31 |         for(i=1;i<=n;i++)cout<<a[i].c;
      |             ^