Deque ADT接口 DEQUEUE.h:
#include <stdlib.h>
#include "Item.h" void DEQUEUEinit(int);
void DEQUEUEerror(void);
Item DEQUEUEheadget(void);
Item DEQUEUEtailget(void);
void DEQUEUEheadput(Item);
void DEQUEUEtailput(Item);
int DEQUEUEisEmpty(void);
int DEQUEUEisFull(void);
Deque ADT接口实现 DEQUEUE.c:
#include "DEQUEUE.h" static Item *q;
static int N,head,tail; void DEQUEUEinit(int maxN)
{
q=malloc(maxN*sizeof(Item));
if(q==NULL)
DEQUEUEerror();
head=;
tail=;
N=maxN;
}
void DEQUEUEerror(void)
{
printf("\n空间可能已满或为空");
exit();
}
Item DEQUEUEheadget(void)
{
if(DEQUEUEisEmpty())
DEQUEUEerror();
Item temp=q[head];
head=(head+)%N;
return temp;
}
Item DEQUEUEtailget(void)
{
if(DEQUEUEisEmpty())
DEQUEUEerror();
tail=(tail-+N)%N;
return q[tail];
}
void DEQUEUEheadput(Item ch)
{
if(DEQUEUEisFull())
DEQUEUEerror();
head=(head-+N)%N;
q[head]=ch;
}
void DEQUEUEtailput(Item ch)
{
if(DEQUEUEisFull())
DEQUEUEerror();
q[tail]=ch;
tail=(tail+)%N;
}
int DEQUEUEisEmpty(void)
{
if(head==tail)
return ;
return ;
}
int DEQUEUEisFull(void)
{
if(((tail+)%N)==head)
return ;
return ;
}
Item.h:
typedef char Item;
主程序 main.c：
#include <stdio.h> int main(void)
{
int N; printf("输入需要申请内存大小:");
if(scanf("%d", &N))
DEQUEUEinit(N);
else
DEQUEUEerror();
getchar();
printf("输入%d个字符",N);
printf("('+'从队头get '*'从队尾get '大写字母'"
"从队头put '小写字母'从队尾put):\n"); while((N=getchar())!='\n')
{
switch(N)
{
case '+':
putchar(DEQUEUEheadget());
break;
case '*':
putchar(DEQUEUEtailget());
break;
default:
if(N>&&N<)
DEQUEUEheadput(N);
else
DEQUEUEtailput(N);
}
} return ;
}