feat: add array_list data structure

fixes #2

lib/array_list.c

@@ -0,0 +1,39 @@
+#include "array_list.h"
+
+struct array_list* array_list_initialization() {
+  struct array_list* list = malloc(sizeof(struct array_list));
+  list->data = malloc(sizeof(void*) * ARRAY_LIST_INITIAL_CAPACITY);
+  list->size = 0;
+  list->capacity = ARRAY_LIST_INITIAL_CAPACITY;
+  return list;
+}
+
+void array_list_add(struct array_list* list, void* element) {
+  if (list->size >= list->capacity) {
+    size_t previous_capacity = list->capacity;
+    list->capacity += ARRAY_LIST_INITIAL_CAPACITY;
+    list->data = realloc(list->data, sizeof(void*) * list->capacity);
+    for (size_t index = previous_capacity; index < list->capacity; index++) {
+      list->data[index] = NULL;
+    }
+  }
+  list->data[list->size] = element;
+  list->size++;
+}
+
+void array_list_remove(struct array_list* list, size_t index) {
+  if (index >= list->size) {
+    return;
+  }
+  for (size_t i = index + 1; i < list->size - 1; i++) {
+    list->data[i - 1] = list->data[i];
+  }
+  list->size--;
+}
+
+void* array_list_get(struct array_list* list, size_t index) {
+  if (index >= list->size) {
+    return NULL;
+  }
+  return list->data[index];
+}

lib/array_list.h

@@ -0,0 +1,25 @@
+#ifndef __ARRAY_LIST__
+#define __ARRAY_LIST__
+
+#include <stdbool.h>
+#include <stdlib.h>
+
+#include "linked_list.h"
+
+#define ARRAY_LIST_INITIAL_CAPACITY 10
+
+struct array_list {
+  void** data;
+  size_t size;
+  size_t capacity;
+};
+
+struct array_list* array_list_initialization();
+
+void array_list_add(struct array_list* list, void* element);
+
+void array_list_remove(struct array_list* list, size_t index);
+
+void* array_list_get(struct array_list* list, size_t index);
+
+#endif