Update cv4/a_train.c

cv4/a_train.c

@@ -1,18 +1,111 @@
-#include "a_train.h"
 #include <stdio.h>
+#define SIZE 50
 
-struct car* add_car(struct car* first,const char* target) {
+
-    return NULL;
+struct car
+{
+    char value[SIZE]; // Cieľová stanica
+    struct car* next; // Ďaľší záznam, môže byť NULL
+};
+
+struct car* add_car(struct car* first,const char* target)
+{
+    struct car* nc=(struct car*) malloc(sizeof(struct car));
+    strcpy(nc->value, target);
+    nc->next=NULL;
+
+    if(first)
+    {
+        while(first->next!=NULL)
+        {    
+            first=first->next;
+        }
+        first->next=nc;
+        return first;
+    }
+    
+    first=nc;  
+
+    return first;
 }
 
-void print_train(struct car* first) {
+void print_train(struct car* first)
+{
+    if(first==NULL)
+    {
+        return;
+    }
+
+    do
+    {
+        printf("%s -> ", first->value);
+        first=first->next;
+    }while(first->next!=NULL);
+
 }
 
-void cancel_train(struct car* first) {
+void cancel_train(struct car* first)
+{
+    struct car* t;
+    while(first!=NULL)
+    {
+        t=first;
+        first=first->next;
+        free(t);
+    }
+}
+
+struct car* clear_train(struct car* first, const char* target)
+{
+    struct car* t;  //змінна для збереження кого видаляти
+
+    if(first==NULL || target==NULL)
+    {
+        return first;
+    }
+
+    //голова == таргет - видаляємо лише перший
+    while(strcmp(first->value, target)==0) //поки рядки однакові
+    {
+        t=first;
+        first=first->next;
+        free(t);
+        if(first==NULL)
+        {
+           return NULL;
+        }
+    }
+
+    //голова не  таргет
+    do
+    {
+        if(strcmp(first->next->value, target)==0)
+        {
+            t=first;
+            first=first->next;
+            free(t);
+        }
+        else
+        {
+            first=first->next;
+        }
+    }
+    while(first);
+	return first;
+}
+
+int main()
+ {
+  struct car* train = NULL;
+  train = add_car(train,"Presov");
+  train = add_car(train,"Bratislava");
+  train = add_car(train,"Levoca");
+  train = add_car(train,"Spiska Nova Ves");
+  print_train(train);
+  clear_train(train,"Levoca");
+  print_train(train);
+  cancel_train(train);
+  return 0;
 }
 
 
-struct car* clear_train(struct car* first, const char* target) {
-	return NULL;
-}
-