Deleting from a Binary Search Tree

[leaden plover]

I just want ideas on how to delete a node from a BST while making sure that the parent pointer (if it has one, which should be all but the root) also points to NULL afterwards

[main condor]

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[leaden plover]

void del_tree_node(node* root, customer* person) {
    if (root == NULL) {
        return;
    }
    int comparison = strcmp(person->name, root->person->name);

    if (comparison < 0) {
        del_tree_node(root->left, person);
    }
    else if (comparison > 0) {
        del_tree_node(root->right, person);
    }
    else {
        if (root->left == NULL && root->right == NULL) {
            printf("%s deleted\n", root->person->name);
            free(root->person->name);
            free(root->person);
            free(root);
            root = NULL;
        }
        else if (root->left == NULL) {
            node* temp = root->right;
            printf("%s deleted\n", root->person->name);
            free(root->person->name);
            free(root->person);
            free(root);
            root = temp;
        }
        else if (root->right == NULL) {
            node* temp = root->left;
            printf("%s deleted\n", root->person->name);
            free(root->person->name);
            free(root->person);
            free(root);
            root = temp;
        }
        else {
            node* max_left_node = left_tree_maximum(root->left);
            customer* temp = root->person;
            root->person = max_left_node->person;
            max_left_node->person = temp;
            del_tree_node(max_left_node, person);
        }
    }
}

That's the function to delete, and I'll post the structs in a moment

typedef struct customer {
    char* name;
    int points;
} customer;

typedef struct tree_node {
    struct customer* person;
    struct tree_node* left;
    struct tree_node* right;
    int depth;
} node;

Ah, i didn't want to work with finding the parent in the function but I figure if I just add a node* parent value to my tree_node struct and set it whenever I create a node it should be fine

!close