86 lines
1.9 KiB
C
86 lines
1.9 KiB
C
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include "a_train.h"
|
|
|
|
/**
|
|
* Prida vozen na koniec vlaku.
|
|
*/
|
|
struct car* add_car(struct car* first, const char* target) {
|
|
// vytvorenie noveho vozna
|
|
struct car* newcar = calloc(1, sizeof(struct car));
|
|
if (newcar == NULL) {
|
|
return first; // ak zlyha alokacia, vrat povodny zoznam
|
|
}
|
|
|
|
strcpy(newcar->value, target);
|
|
newcar->next = NULL;
|
|
|
|
// ak je vlak prazdny
|
|
if (first == NULL) {
|
|
return newcar;
|
|
}
|
|
|
|
// najdi posledny vozen
|
|
struct car* this = first;
|
|
while (this->next != NULL) {
|
|
this = this->next;
|
|
}
|
|
|
|
// pripoj novy vozen
|
|
this->next = newcar;
|
|
return first;
|
|
}
|
|
|
|
/**
|
|
* Vypise vsetky vozne vo vlaku.
|
|
*/
|
|
void print_train(struct car* first) {
|
|
struct car* this = first;
|
|
while (this != NULL) {
|
|
printf("%s\n", this->value);
|
|
this = this->next;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Zrusenie vsetkych voznov vo vlaku.
|
|
*/
|
|
void cancel_train(struct car* first) {
|
|
if (first == NULL) return;
|
|
|
|
// rekurzivne uvolnenie
|
|
cancel_train(first->next);
|
|
free(first);
|
|
}
|
|
|
|
/**
|
|
* Vyradenie vsetkych voznov, ktorych cielova stanica je target.
|
|
*/
|
|
struct car* clear_train(struct car* first, const char* target) {
|
|
struct car* current = first;
|
|
struct car* prev = NULL;
|
|
|
|
while (current != NULL) {
|
|
if (strcmp(current->value, target) == 0) {
|
|
// treba zmazat tento vozen
|
|
struct car* to_delete = current;
|
|
if (prev == NULL) {
|
|
// mazeme prvy prvok
|
|
first = current->next;
|
|
} else {
|
|
// mazeme stredny alebo posledny prvok
|
|
prev->next = current->next;
|
|
}
|
|
current = current->next;
|
|
free(to_delete);
|
|
} else {
|
|
// presun dalej
|
|
prev = current;
|
|
current = current->next;
|
|
}
|
|
}
|
|
|
|
return first;
|
|
}
|