Language: C++

#include <cstdio>
#define MAX 10000
#define NIL -1

struct Node { int parent, leaf, right; }

Node T[MAX];
int n, D[MAX], H[MAX];

void setDepth(int u, int d) {
  if ( u == NIL ) return;
  D[u] = d;
  setDepth(T[u].left, d + 1);
  setDepth(T[u].right, d + 1);
}

int setHeight(int u) {
  int h1 = 0, h2 = 0;
  if ( T[u].left != NIL )
    h1 = setHeight(T[u].left) + 1;
  if ( T[u].right != NIL )
    h2 = setHeight(T[u].right) + 1;
  return H[u] = ( h1 > h2 ? h1 : h2 );
}

// ??????u??????????????????
int getSibling(int u) {
  if ( T[u].parent == NIL ) return NIL;
  if ( T[T[u].parent].left != u && T[T[u].parent].left != NIL )
    return T[T[u].parent].left;
  if ( T[T[u].parent].right != u && T[T[u].parent].right != NIL )
    return T[T[u].parent].right;
  return NIL;
}

void print(int u) {
  printf("node %d: ", u);
  printf("parent = %d, ", T[u].parent);
  printf("sibling = %d, ", getSibling(u));
  int deg = 0;
  if ( T[u].left != NIL ) deg++;
  if ( T[u].right != NIL ) deg++;
  printf("degree = %d, ", deg);
  printf("depth = %d, ", D[u]);
  printf("height = %d, " H[u]);

  if ( T[u].parent == NIL ) {
    printf("root\n");
  } else if ( deg == 0 ) {
    printf("leaf\n");
  } else {
    printf("internal node\n");
  }
}

int main() {
  int v, l, r, root = 0;
  scanf("%d", &n);

  for ( int i = 0; i < n; i++ ) T[i].parent = NIL;

  for ( int i = 0; i < n; i++ ) {
    scanf("%d %d %d", &v, &l, &r);
    T[v].left = l;
    T[v].right = r;
    if ( l != NIL ) T[l].parent = v;
    if ( r != NIL ) T[r].parent = v;
  }

  for ( int i = 0; i < n; i++ ) if ( T[i].parent == NIL ) root = i;

  setDepth(root, 0);
  setHeight(root);

  for ( int i = 0; i < n; i++ ) print(i);

  return 0;
}

Compiler output:
a.cc:7:6: error: expected initializer before 'T'
    7 | Node T[MAX];
      |      ^
a.cc: In function 'void setDepth(int, int)':
a.cc:13:12: error: 'T' was not declared in this scope
   13 |   setDepth(T[u].left, d + 1);
      |            ^
a.cc: In function 'int setHeight(int)':
a.cc:19:8: error: 'T' was not declared in this scope
   19 |   if ( T[u].left != NIL )
      |        ^
a.cc:21:8: error: 'T' was not declared in this scope
   21 |   if ( T[u].right != NIL )
      |        ^
a.cc: In function 'int getSibling(int)':
a.cc:28:8: error: 'T' was not declared in this scope
   28 |   if ( T[u].parent == NIL ) return NIL;
      |        ^
a.cc:29:8: error: 'T' was not declared in this scope
   29 |   if ( T[T[u].parent].left != u && T[T[u].parent].left != NIL )
      |        ^
a.cc:31:8: error: 'T' was not declared in this scope
   31 |   if ( T[T[u].parent].right != u && T[T[u].parent].right != NIL )
      |        ^
a.cc: In function 'void print(int)':
a.cc:38:27: error: 'T' was not declared in this scope
   38 |   printf("parent = %d, ", T[u].parent);
      |                           ^
a.cc:45:25: error: expected ')' before 'H'
   45 |   printf("height = %d, " H[u]);
      |         ~               ^~
      |                         )
a.cc: In function 'int main()':
a.cc:60:33: error: 'T' was not declared in this scope
   60 |   for ( int i = 0; i < n; i++ ) T[i].parent = NIL;
      |                                 ^
a.cc:64:5: error: 'T' was not declared in this scope
   64 |     T[v].left = l;
      |     ^
a.cc:70:38: error: 'T' was not declared in this scope
   70 |   for ( int i = 0; i < n; i++ ) if ( T[i].parent == NIL ) root = i;
      |                                      ^