Добавить du6/list_ops.c

du6/list_ops.c

@@ -0,0 +1,103 @@
+#include "list_ops.h"
+#include <string.h>
+
+// constructs a new list
+list_t *new_list(size_t length, list_element_t elements[]) {
+    list_t *list = (list_t *)malloc(sizeof(list_t) + length * sizeof(list_element_t));
+    if (!list) {
+        return NULL;
+    }
+    list->length = length;
+    memcpy(list->elements, elements, length * sizeof(list_element_t));
+    return list;
+}
+
+// append entries to a list and return the new list
+list_t *append_list(list_t *list1, list_t *list2) {
+    size_t new_length = list1->length + list2->length;
+    list_t *new_list = (list_t *)malloc(sizeof(list_t) + new_length * sizeof(list_element_t));
+    if (!new_list) {
+        return NULL;
+    }
+    new_list->length = new_length;
+    memcpy(new_list->elements, list1->elements, list1->length * sizeof(list_element_t));
+    memcpy(new_list->elements + list1->length, list2->elements, list2->length * sizeof(list_element_t));
+    return new_list;
+}
+
+// filter list returning only values that satisfy the filter function
+list_t *filter_list(list_t *list, bool (*filter)(list_element_t)) {
+    list_element_t *temp = (list_element_t *)malloc(list->length * sizeof(list_element_t));
+    if (!temp) {
+        return NULL;
+    }
+    size_t count = 0;
+    for (size_t i = 0; i < list->length; i++) {
+        if (filter(list->elements[i])) {
+            temp[count++] = list->elements[i];
+        }
+    }
+    list_t *filtered_list = (list_t *)malloc(sizeof(list_t) + count * sizeof(list_element_t));
+    if (!filtered_list) {
+        free(temp);
+        return NULL;
+    }
+    filtered_list->length = count;
+    memcpy(filtered_list->elements, temp, count * sizeof(list_element_t));
+    free(temp);
+    return filtered_list;
+}
+
+// returns the length of the list
+size_t length_list(list_t *list) {
+    return list->length;
+}
+
+// return a list of elements whose values equal the list value transformed by the mapping function
+list_t *map_list(list_t *list, list_element_t (*map)(list_element_t)) {
+    list_t *mapped_list = (list_t *)malloc(sizeof(list_t) + list->length * sizeof(list_element_t));
+    if (!mapped_list) {
+        return NULL;
+    }
+    mapped_list->length = list->length;
+    for (size_t i = 0; i < list->length; i++) {
+        mapped_list->elements[i] = map(list->elements[i]);
+    }
+    return mapped_list;
+}
+
+// folds (reduces) the given list from the left with a function
+list_element_t foldl_list(list_t *list, list_element_t initial, list_element_t (*foldl)(list_element_t, list_element_t)) {
+    list_element_t result = initial;
+    for (size_t i = 0; i < list->length; i++) {
+        result = foldl(result, list->elements[i]);
+    }
+    return result;
+}
+
+// folds (reduces) the given list from the right with a function
+list_element_t foldr_list(list_t *list, list_element_t initial, list_element_t (*foldr)(list_element_t, list_element_t)) {
+    list_element_t result = initial;
+    for (size_t i = list->length; i > 0; i--) {
+        result = foldr(list->elements[i - 1], result);
+    }
+    return result;
+}
+
+// reverse the elements of the list
+list_t *reverse_list(list_t *list) {
+    list_t *reversed_list = (list_t *)malloc(sizeof(list_t) + list->length * sizeof(list_element_t));
+    if (!reversed_list) {
+        return NULL;
+    }
+    reversed_list->length = list->length;
+    for (size_t i = 0; i < list->length; i++) {
+        reversed_list->elements[i] = list->elements[list->length - i - 1];
+    }
+    return reversed_list;
+}
+
+// destroy the entire list
+void delete_list(list_t *list) {
+    free(list);
+}