41 lines
834 B
C
41 lines
834 B
C
#include "queue.h"
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struct queue *enqueue(struct queue *queue, struct expression_element* element) {
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struct queue *new_elt = calloc(1,sizeof(struct queue));
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new_elt->data = element;
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if(!queue)
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return new_elt;
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struct queue* current = queue;
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while(current->next)
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current = current->next;
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current->next = new_elt;
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return queue;
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}
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struct expression_element* dequeue(struct queue **queue) {
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if (!queue || !*queue)
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return NULL;
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struct queue* removed = *queue;
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struct expression_element* res = removed->data;
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*queue = removed->next;
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free(removed);
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return res;
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}
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void queue_destroy(struct queue **queue) {
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if(!queue)
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return;
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while (*queue) {
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struct expression_element* dequeued = dequeue(queue);
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free(dequeued);
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}
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} |