Binary Search Tree (BST) Create, search, height, search path length

#include <stdio.h>
#include <stdlib.h>

struct Node {
    struct Node* lchild;
    int data;
    struct Node* rchild;
}*root = NULL;
void Insert(int key) {
    struct Node* t = root;
    struct Node* r = NULL, * p;

    if (root == NULL) {
        p = (struct Node*)malloc(sizeof(struct Node));
        p->data = key;
        p->lchild = p->rchild = NULL;
        root = p;
        return;
    }
    while (t != NULL) {
        r = t;
        if (key < t->data)
            t = t->lchild;
        else if (key > t->data)
            t = t->rchild;
        else
            return;
    }
    p = (struct Node*)malloc(sizeof(struct Node));
    p->data = key;
    p->lchild = p->rchild = NULL;

    if (key < r->data) r->lchild = p;
    else r->rchild = p;
}
void Inorder(struct Node* p) {
    if (p) {
        Inorder(p->lchild);
        printf("%d ", p->data);
        Inorder(p->rchild);
    }
}
struct Node* Search(int key) {
    struct Node* t = root;

    while (t != NULL) {
        if (key == t->data)
            return t;
        else if (key < t->data)
            t = t->lchild;
        else
            t = t->rchild;
    }
    return NULL;
}

int SearchPathLength(int key) {
    struct Node* t = root;
    static int counter = 0;
    while (t != NULL) {
        if (key == t->data)
            return counter;
        else if (key < t->data)
        {
            counter++;
            t = t->lchild;
        }
        else
        {
            counter++;
            t = t->rchild;
        }
    }
    return 0;
}

int Height(struct Node* p)
{
    int x, y;
    if (p == NULL)return 0;
    x = Height(p->lchild);
    y = Height(p->rchild);
    return x > y ? x +1 : y + 1;
}
int main() {
    struct Node* temp;

    Insert(50);
    Insert(10);
    Insert(30);
    Insert(40);
    Insert(20);

    Inorder(root);
    printf("\n");

    temp = Search(20);
    if (temp != NULL)
        printf("element %d is found\n", temp->data);
    else
        printf("element is not found\n");
    int pathLevels = SearchPathLength(30);
    printf("The length is %d \n", pathLevels);
    printf("The height of the tree is %d \n", Height(root));
    return 0;
}