Sync LeetCode submission - N-ary Tree Preorder Traversal (c)

Author: JMoogs

my-folder/problems/n-ary_tree_preorder_traversal/solution.c

@@ -0,0 +1,58 @@
+#include <stdio.h>
+#include <stdlib.h>
+struct DynArray {
+	int* mem;
+	int size;
+	int capacity;
+};
+
+struct DynArray* createDynArray(int);
+void pushDynArray(struct DynArray*, int);
+void preorder_recurse(struct DynArray*, struct Node*);
+
+int* preorder(struct Node* root, int* returnSize) {
+	struct DynArray* return_array = createDynArray(8);
+	preorder_recurse(return_array, root);
+	int* mem = return_array->mem;
+	*returnSize = return_array->size;
+	// Free the dynamic array structure after extracting the required info
+	free((void*) return_array);
+	return mem;
+}
+
+void preorder_recurse(struct DynArray* ret_arr, struct Node* tree) {
+	if (!tree) {
+		return;
+	}
+	
+	// Root
+	pushDynArray(ret_arr, tree->val);
+	// Others from left to right
+	for (int i = 0; i < tree->numChildren; ++i) {
+		preorder_recurse(ret_arr, *(tree->children + i));
+	}
+
+}
+
+struct DynArray* createDynArray(int start_size) {
+	struct DynArray* arr = malloc(sizeof(struct DynArray));
+	int* arr_mem = malloc(start_size * sizeof(int));
+
+	arr->mem = arr_mem;
+	arr->capacity = start_size;
+	arr->size = 0;
+
+	return arr;
+}
+
+void pushDynArray(struct DynArray* arr, int val) {
+	if (arr->size == arr->capacity) {
+		int* mem = (int*) realloc((void*) arr->mem, 2 * arr->capacity * sizeof(int));
+		arr->mem = mem;
+        arr->capacity *= 2;
+	}
+	*(arr->mem + arr->size) = val;
+	++(arr->size);
+	return;
+
+}