foo.cc:8:2: error: expected ‘;’ after struct definition
    8 | }[1005];
      |  ^
      |  ;
foo.cc:8:2: error: expected unqualified-id before ‘[’ token
foo.cc: In function ‘void dfs(int, int)’:
foo.cc:13:13: error: ‘a’ was not declared in this scope
   13 |         dfs(a[u].l,dep+1);
      |             ^
foo.cc: In function ‘int main()’:
foo.cc:22:22: error: ‘a’ was not declared in this scope
   22 |                 cin>>a[i].l>>a[i].r;
      |                      ^