usaa19exam/a_station.c

#include "a_station.h"
#include <stdlib.h>
#include <string.h>

struct station* create_station(){
   struct station* station = calloc(1,sizeof(struct station));
   station->tracks = calloc(STATION_SIZE, sizeof(struct car*));
   station->capacity = STATION_SIZE;
   return station;
}

void destroy_station(struct station* station){
   for (int i = 0; i < station->capacity; i++){
        /// Jedna polozka je spojkovy zoznam, uvolni cely spojkovy zoznam
        struct car* list = station->tracks[i];
        while (list != NULL){
            struct car* del = list;
            list = del->next;
            free(del);
        }
    }
    free(station->tracks);
    free(station);
}

int select_track(struct station* station, const char* target){
   unsigned int hash = 0;
    for (int counter = 0; target[counter]!='\0'; counter++){
        hash = target[counter] + (hash << 6) + (hash << 16) - hash;
    }

   if(hash < 0 || hash > station->capacity){
      hash = hash % station->capacity;
   }
    return hash;
}

void add_target_capacity(struct station* station,const char* target, int capacity){
   int slot_index = select_track(station,target);

   struct car* slot = station->tracks[slot_index];
   while (slot != NULL){
      if(strcmp(slot->value,target) == 0){
         //strcpy(slot->value, target);
         slot->capacity += capacity;
         return;
      }
      slot = slot->next;
   }
   struct car* new = malloc(sizeof(struct car));
    strcpy(new->value,target);
    new->capacity = capacity;
    new->next = slot;
    station->tracks[slot_index] = new;
    if (new->next){
        return;
    }
    return;
    
}

int get_target_capacity(struct station* station,const char* target){
   int slot_index = select_track(station, target);
   struct car* car = station->tracks[slot_index];
   while(car != NULL){
      if(strcmp(car->value,target)== 0){
         return car->capacity;
      }
      car = car->next;
   }
	return -1;
}

int count_targets(struct station* station){
   int num_of_targets = 0;
   for(int i = 0; i < STATION_SIZE; i++){
      if(station->tracks[i] != NULL) num_of_targets++;
   }
	return num_of_targets;
}

int count_capacity(struct station* station){
	int sum_capacity = 0;

   for(int i = 0; i < STATION_SIZE; i++){
      struct car* train = station->tracks[i];
      while(train != NULL){
         sum_capacity += train->capacity;
         train = train->next;
      }
   }
   
   return sum_capacity;
   
}