diff --git a/cv4/a_train.c b/cv4/a_train.c
index 3ecfbc8..e4ca71c 100644
--- a/cv4/a_train.c
+++ b/cv4/a_train.c
@@ -1,18 +1,63 @@
-#include "a_train.h"
 #include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include "a_train.h"
 
-struct car* add_car(struct car* first,const char* target) {
-    return NULL;
+struct car* add_car(struct car* first, const char* target){
+    if(!strcmp(target, "") && !first)
+        return NULL;
+
+    struct car* temp = first;
+
+    while(temp->next != NULL)
+        temp = temp->next;
+
+    temp->next = (struct car*)calloc(1, sizeof(struct car));
+    strcpy(temp->next->value, target);
+    temp->next->next = NULL;
+    return first;
 }
 
-void print_train(struct car* first) {
+void print_train(struct car* first){
+    struct car* temp = first;
+
+    while(temp != NULL){
+        printf("%s\n", temp->value);
+        temp = temp->next;
+    }
 }
 
-void cancel_train(struct car* first) {
+void cancel_train(struct car* first){
+    if(!first)
+        return;
+
+    struct car* temp = first;
+    struct car* next = temp->next;
+
+    while(next != NULL){
+        next = temp->next;
+        free(temp);
+        temp = next;
+    }
+
+    first = NULL;
 }
 
+struct car* clear_train(struct car* first, const char* target){
+    if(!first || !strcmp(target, ""))
+        return NULL;
 
-struct car* clear_train(struct car* first, const char* target) {
-	return NULL;
-}
+    struct car* temp = first;
+    struct car* next = temp->next;
 
+    while(next != NULL){
+        next = temp->next;
+        if(!strcmp(temp->value, target))
+            free(temp);
+        temp = next;
+        if(!first)
+            first = temp;
+    }
+
+    return first;
+}
\ No newline at end of file