Language: C

#inlude <stdio.h>
#define MAX 10000
#define NIL -1

struct Node { int p, l, r;};
struct Node T{MAX};
int n;

void preParse(int u) {
  if(u == NIL)
    return;
  printf(" %d", u);
  preParse(T[u].l);
  preParse(T[u].r);
}

void inParse(int u) {
  if(u == NIL)
    return;
  inParse(T[u].l);
  printf(" %d", u);
  inparse(T[u].r);
}

void postParse(int u) {
  if(u == NIL)
    return;
  postParse(T[u].l);
  postParse(T[u].r);
  printf(" %d", u);
}

int main(void)
{
  int i, v, l, r, root;

  scanf("%d", &n);
  for(i = 0; i < n; i++) {
    T[i].p = NIL;
  }

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

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

  printf("Preorder\n");
  preParse(root);
  printf("\n");
  printf("Inorder\n");
  inParse(root);
  printf("\n");
  printf("Postorder\n");
  postParse(root);
  printf("\n");

  return 0;
}

Compiler output:
main.c:1:2: error: invalid preprocessing directive #inlude; did you mean #include?
    1 | #inlude <stdio.h>
      |  ^~~~~~
      |  include
main.c:6:14: error: expected '=', ',', ';', 'asm' or '__attribute__' before '{' token
    6 | struct Node T{MAX};
      |              ^
main.c: In function 'preParse':
main.c:12:3: error: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
   12 |   printf(" %d", u);
      |   ^~~~~~
main.c:1:1: note: include '<stdio.h>' or provide a declaration of 'printf'
  +++ |+#include <stdio.h>
    1 | #inlude <stdio.h>
main.c:12:3: warning: incompatible implicit declaration of built-in function 'printf' [-Wbuiltin-declaration-mismatch]
   12 |   printf(" %d", u);
      |   ^~~~~~
main.c:12:3: note: include '<stdio.h>' or provide a declaration of 'printf'
main.c:13:12: error: 'T' undeclared (first use in this function)
   13 |   preParse(T[u].l);
      |            ^
main.c:13:12: note: each undeclared identifier is reported only once for each function it appears in
main.c: In function 'inParse':
main.c:20:11: error: 'T' undeclared (first use in this function)
   20 |   inParse(T[u].l);
      |           ^
main.c:21:3: warning: incompatible implicit declaration of built-in function 'printf' [-Wbuiltin-declaration-mismatch]
   21 |   printf(" %d", u);
      |   ^~~~~~
main.c:21:3: note: include '<stdio.h>' or provide a declaration of 'printf'
main.c:22:3: error: implicit declaration of function 'inparse'; did you mean 'inParse'? [-Wimplicit-function-declaration]
   22 |   inparse(T[u].r);
      |   ^~~~~~~
      |   inParse
main.c: In function 'postParse':
main.c:28:13: error: 'T' undeclared (first use in this function)
   28 |   postParse(T[u].l);
      |             ^
main.c:30:3: warning: incompatible implicit declaration of built-in function 'printf' [-Wbuiltin-declaration-mismatch]
   30 |   printf(" %d", u);
      |   ^~~~~~
main.c:30:3: note: include '<stdio.h>' or provide a declaration of 'printf'
main.c: In function 'main':
main.c:37:3: error: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
   37 |   scanf("%d", &n);
      |   ^~~~~
main.c:37:3: note: include '<stdio.h>' or provide a declaration of 'scanf'
main.c:37:3: warning: incompatible implicit declaration of built-in function 'scanf' [-Wbuiltin-declaration-mismatch]
main.c:37:3: note: include '<stdio.h>' or provide a declaration of 'scanf'
main.c:39:5: error: 'T' undeclared (first use in this function)
   39 |     T[i].p = NIL;
      |     ^
main.c:42:8: error: expected ';' before numeric constant
   42 |   for(i  0; i < n; i++) {
      |        ^ ~
      |        ;
main.c:53:12: error: expected ')' before 'p'
   53 |     if(T[i]p == NIL)
      |       ~    ^
      |            )
main.c:56:3: warning: incompatible implicit declaration of built-in function 'printf' [-Wbuiltin-declaration-mismatch]
   56 |   printf("Preorder\n");
      |   ^~~~~~
main.c:56:3: note: include '<stdio.h>' or provide a declaration of 'printf'