usaa20/cv6/a_station.c
Maryna Kravtsova 3734bd0fdb station
2020-11-07 16:52:33 +01:00

110 lines
3.0 KiB
C

#include "a_station.h"
#include <stdlib.h>
#include <string.h>
struct station* create_station(){
struct station* station = (struct station*)calloc(1,sizeof(struct station));
station->tracks = (struct car**)calloc(STATION_SIZE, sizeof(struct car*));
station->track_count = STATION_SIZE;
return station;
}
void destroy_station(struct station* station){
for(int i = 0; i < station->track_count; i++){
//get one linked list from station
struct car* this = station->tracks[i];
while(this != NULL){
struct car* delete = this;
this = delete->next;
free(delete);
}
}
free(station->tracks);
free(station);
}
int select_track(struct station* station, const char* target){
unsigned int hash = 0;
for(int i = 0; target[i] != '\0'; i++){
//i used "lose lose" function, because it's simple and clear
hash += target[i];
}
//change hash, so that it will be between 0 and station->track_count
hash = hash % station->track_count;
return hash;
}
void add_target_capacity(struct station* station,const char* target, int capacity){
//find hash
int track = select_track(station, target);
//get right linked list(with help of hash)
struct car* start = station->tracks[track];
while(start != NULL){
int x = strcmp(start->value, target);
//if the "wagon" track is similar to the target, then increment capacity
if(x == 0){
start->capacity = start->capacity + capacity;
return;
}
start = start->next;
}
//if track is empty, create new "wagon"
if(station->tracks[track] == NULL){
struct car* new = calloc(1, sizeof(struct car));
strcpy(new->value, target);
new->capacity = capacity;
new->next = start;
station->tracks[track] = new;
/*if(new->next){
return;
}*/
}
return;
}
int get_target_capacity(struct station* station,const char* target){
//find hash
int track = select_track(station, target);
//get right linked list
struct car* start = station->tracks[track];
while(start != NULL){
int x = strcmp(start->value, target);
//if the target is similar to "wagon", than get the capacity
if(x == 0){
return start->capacity;
}
start = start->next;
}
return 0;
}
//count all tracks
int count_targets(struct station* station){
int targets = 0;
for(int i = 0; i < STATION_SIZE; i++){
if(station->tracks[i] != NULL){
targets++;
}
}
return targets;
}
//count capacity in all tracks
int count_capacity(struct station* station){
int capacity = 0;
for(int i = 0; i < STATION_SIZE; i++){
//get one linked list and count there capacity
struct car* this = station->tracks[i];
if(this != NULL){
capacity = capacity + this->capacity;
this = this->next;
}
}
return capacity;
}