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

typedef struct _BSTNode {
    struct _BSTNode* left;
    struct _BSTNode* right;
    int value;
} BSTNode;

// if you include level and side for a pre-order print,
// can be good for debugging your tree strucutre
void print_pre_order(BSTNode* root, int level, char side) {
    if (root != NULL) {
        for (int i = 0; i < level; i++) {
            fputc(' ', stdout);
        }
        printf("%c: %d\n", side, root->value);
        print_pre_order(root->left, level + 1, 'L');
        print_pre_order(root->right, level + 1, 'R');
    }
}

// best for printing the full sorted tree, or transferring it to
// an array
void print_in_order(BSTNode* root) {
    if (root != NULL) {
        print_in_order(root->left);
        printf("%d\n", root->value);
        print_in_order(root->right);
    }
}

void destroy_bst(BSTNode* root) {
    if (root != NULL) {
        destroy_bst(root->left);
        destroy_bst(root->right);
        free(root);
    }
}

int main(int argc, char* argv[]) {
    BSTNode* root = NULL;

    BSTNode* new_node = malloc(sizeof(*new_node));
    *new_node = (BSTNode) { .value = 5, .left = NULL, .right = NULL };
    root = new_node;

    new_node = malloc(sizeof(*new_node));
    *new_node = (BSTNode) { .value = 3, .left = NULL, .right = NULL };
    root->left = new_node;

    new_node = malloc(sizeof(*new_node));
    *new_node = (BSTNode) { .value = 8, .left = NULL, .right = NULL };
    root->right = new_node;

    new_node = malloc(sizeof(*new_node));
    *new_node = (BSTNode) { .value = 1, .left = NULL, .right = NULL };
    root->left->left = new_node;

    new_node = malloc(sizeof(*new_node));
    *new_node = (BSTNode) { .value = 4, .left = NULL, .right = NULL };
    root->left->right = new_node;

    new_node = malloc(sizeof(*new_node));
    *new_node = (BSTNode) { .value = 9, .left = NULL, .right = NULL };
    root->right->right = new_node;

    print_pre_order(root, 0, 'R');
    print_in_order(root);

    destroy_bst(root);

    return EXIT_SUCCESS;
}
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