mohlo by fungovat

du6/list_ops.c

@@ -1 +1,155 @@
 #include "list_ops.h"
+
+#ifndef LIST_OPS_H
+#define LIST_OPS_H
+
+#include <stdlib.h>
+#include <stdbool.h>
+
+typedef int list_element_t;
+
+typedef struct {
+   size_t length;
+   list_element_t elements[];
+} list_t;
+
+// constructs a new list
+list_t *new_list(size_t length, list_element_t elements[]);
+
+// append entries to a list and return the new list
+list_t *append_list(list_t *list1, list_t *list2);
+
+// filter list returning only values that satisfy the filter function
+list_t *filter_list(list_t *list, bool (*filter)(list_element_t));
+
+// returns the length of the list
+size_t length_list(list_t *list);
+
+// 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));
+
+// 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));
+
+// 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));
+
+// reverse the elements of the list
+list_t *reverse_list(list_t *list);
+
+// destroy the entire list
+// list will be a dangling pointer after calling this method on it
+void delete_list(list_t *list);
+
+#endif
+
+#include "list_ops.h"
+
+
+void delete_list(list_t *list) {
+    free(list);
+}
+
+list_t *new_list(size_t length, list_element_t elements[]) {
+
+    // Calculate the memory size
+    size_t size = sizeof(list_t) + length * sizeof(list_element_t);
+
+    // Allocate memory
+    list_t *list = malloc(size);
+
+    if (list == NULL) {
+        return NULL; // Check if allocation failed
+    }
+
+    // Set the length of the list
+    list->length = length;
+
+    // Copy the input elements to the list
+    for (size_t i = 0; i < length; i++) {
+        list->elements[i] = elements[i];
+    }
+
+    return list;
+}
+
+size_t length_list(list_t *list) {
+    return list->length;
+}
+
+list_t *append_list(list_t *list1, list_t *list2) {
+    size_t new_length = list1->length + list2->length;
+    list_element_t new_elements[new_length];
+
+    for (size_t i = 0; i < list1->length; ++i) {
+        new_elements[i] = list1->elements[i];
+    }
+
+    for (size_t i = 0; i < list2->length; ++i) {
+        new_elements[list1->length + i] = list2->elements[i];
+    }
+
+    return new_list(new_length, new_elements);
+}
+
+list_t *reverse_list(list_t *list) {
+    list_element_t reversed_elements[list->length];
+
+    for (size_t i = 0; i < list->length; ++i) {
+        reversed_elements[i] = list->elements[list->length - 1 - i];
+    }
+
+    return new_list(list->length, reversed_elements);
+}
+
+list_t *map_list(list_t *list, list_element_t (*map)(list_element_t)) {
+    list_element_t mapped_elements[list->length];
+
+    for (size_t i = 0; i < list->length; i++) {
+        mapped_elements[i] = map(list->elements[i]);
+    }
+
+    return new_list(list->length, mapped_elements);
+}
+
+list_t *filter_list(list_t *list, bool (*filter)(list_element_t)) {
+    list_element_t filtered_elements[list->length];
+    size_t count = 0;
+
+    for (size_t i = 0; i < list->length; i++) {
+        if (filter(list->elements[i])) {
+            filtered_elements[count++] = list->elements[i];
+        }
+    }
+
+    return new_list(count, filtered_elements);
+}
+
+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;  // Start with initial value
+
+    // Traverse the list from last to first
+    for (size_t i = 0; i < list->length; ++i) {
+        result = foldr(list->elements[list->length - 1 - i], result);
+    }
+
+    return result;
+}
+
+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;  // Start with initial value
+
+    // Traverse the list from first to last
+    for (size_t i = 0; i < list->length; ++i) {
+        result = foldl(result, list->elements[i]);
+    }
+
+    return result;
+}