73 lines
1.0 KiB
C
73 lines
1.0 KiB
C
#include <stdio.h>
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#include <stdlib.h>
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#include "queue.h"
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queue *qu_create( )
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{
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queue *sq;
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sq = malloc(sizeof(*sq));
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if (NULL == sq)
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return NULL;
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sq->head = 0;
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sq->tail = 0;
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return sq;
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}
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int qu_isempty(queue *sq)
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{
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return (sq->head == sq->tail);
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}
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int qu_enqueue(queue *sq, datatype *x)
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{
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if ((sq->tail + 1) % MAXSIZE == sq->head)
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return -1;
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sq->tail = (sq->tail + 1) % MAXSIZE;
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sq->data[sq->tail] = *x;
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return 0;
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}
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int qu_dequeue(queue *sq, datatype *x)
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{
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if (qu_isempty(sq))
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return -1;
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sq->head = (sq->head + 1) % MAXSIZE;
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*x = sq->data[sq->head];
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return 0;
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}
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void qu_travel(queue *sq)
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{
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if (sq->head == sq->tail)
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return;
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int i;
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i = (sq->head + 1) % MAXSIZE;
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while (i != sq->tail)
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{
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printf("%d ", sq->data[i]);
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i = (i + 1) % MAXSIZE;
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}
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printf("%d \n", sq->data[i]);
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}
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void qu_clear(queue *sq)
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{
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sq->head = sq->tail;
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}
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void qu_destroy(queue *sq)
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{
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free(sq);
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}
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