generated from freudenreichan/info2Praktikum-DobleSpiel
53 lines
1.2 KiB
C
53 lines
1.2 KiB
C
#include <stdlib.h>
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#include "stack.h"
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//TODO: grundlegende Stackfunktionen implementieren:
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/* * `push`: legt ein Element oben auf den Stack,
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* `pop`: entfernt das oberste Element,
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* `top`: liefert das oberste Element zurück,
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* `clearStack`: gibt den gesamten Speicher frei. */
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// Pushes data as pointer onto the stack.
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StackNode *push(StackNode *stack, void *data)
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{
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StackNode *new=malloc(sizeof(StackNode));
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if(new ==NULL){
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return new;
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}
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new->data = data;
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new->dannach = stack;
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return new;
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}
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// Deletes the top element of the stack (latest added element) and releases its memory. (Pointer to data has to be
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// freed by caller.)
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StackNode *pop(StackNode *stack)
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{
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if(stack == NULL){
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return NULL;
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}
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StackNode *new;
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new = stack->dannach;
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free(stack);
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return new;
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}
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// Returns the data of the top element.
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void *top(StackNode *stack)
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{
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if(stack == NULL){
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return NULL;
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}
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return stack->data;
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}
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// Clears stack and releases all memory.
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void clearStack(StackNode *stack)
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{
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while (stack != NULL) {
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StackNode *next = stack->dannach;
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free(stack);
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stack = next;
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}
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} |