diff --git a/a_station.c b/a_station.c
index 931980f..7647b32 100644
--- a/a_station.c
+++ b/a_station.c
@@ -20,13 +20,48 @@ void destroy_station(struct station* station){
         }
         free(station->tracks[i]);
     }
+    free(station);
 }
 
 int select_track(struct station* station, const char* target){
+    int c;
+    int hash = station->capacity;
+    char* str = target;
+    while (c = *str++){
+        hash = ((hash << 5) + hash) + c; /* hash * 33 + c */
+
+        return hash;
+    }
 	return 0;
 }
 
 void add_target_capacity(struct station* station,const char* target, int capacity){
+
+    int track = select_track(station,target);
+    struct car* start = station->tracks[track];
+    if(start == NULL){
+        start->value = target;
+        start->capacity = capacity;
+        start->next = NULL;
+    
+    }else{
+        while(start->next != NULL){
+            if(strcmp(start->value,target)==0){
+                start->capacity = capacity;
+            }
+            start = start->next;
+            if(start->next == NULL){
+                struct car* this =(struct car*)malloc(sizeof(struct car));
+                this->value = target;
+                this->capacity = capacity;
+                this->next = NULL;
+                start->next = this;
+                free(this);
+            }
+        }
+    }
+
+
 }
 
 int get_target_capacity(struct station* station,const char* target){