Add cv4/a_train.c

cv4/a_train.c

@@ -0,0 +1,80 @@
+#include "a_train.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+struct car* add_car(struct car* first, const char* target) {
+    struct car* newcar = (struct car*)calloc(1, sizeof(struct car));
+    if (newcar == NULL) {
+        printf("Ошибка: не удалось выделить память.\n");
+        exit(1);
+    }
+
+    strcpy(newcar->value, target);
+    newcar->next = NULL;
+
+    if (first == NULL) {
+        return newcar;
+    }
+
+    struct car* current = first;
+    while (current->next != NULL) {
+        current = current->next;
+    }
+
+    current->next = newcar;
+    return first;
+}
+
+
+void print_train(struct car* first) {
+    struct car* current = first;
+
+    if (current == NULL) {
+        printf("Поезд пуст.\n");
+        return;
+    }
+
+    while (current != NULL) {
+        printf("%s\n", current->value);
+        current = current->next;
+    }
+}
+
+
+void cancel_train(struct car* first) {
+    if (first == NULL) {
+        return;
+    }
+
+    cancel_train(first->next);
+    free(first);
+}
+
+
+struct car* clear_train(struct car* first, const char* target) {
+    struct car* prev = NULL;
+    struct car* current = first;
+
+    while (current != NULL) {
+        if (strcmp(current->value, target) == 0) {
+            if (prev == NULL) {
+                struct car* temp = current->next;
+                free(current);
+                current = temp;
+                first = current;
+            } else {
+                prev->next = current->next;
+                free(current);
+                current = prev->next;
+            }
+        } else {
+            prev = current;
+            current = current->next;
+        }
+    }
+
+    return first;
+}
+