Deque ADT接口 DEQUEUE.h:
1 #include <stdlib.h>
2 #include "Item.h"
3
4 void DEQUEUEinit(int);
5 void DEQUEUEerror(void);
6 Item DEQUEUEheadget(void);
7 Item DEQUEUEtailget(void);
8 void DEQUEUEheadput(Item);
9 void DEQUEUEtailput(Item);
10 int DEQUEUEisEmpty(void);
11 int DEQUEUEisFull(void);
Deque ADT接口实现 DEQUEUE.c:
1 #include "DEQUEUE.h"
2
3 static Item *q;
4 static int N,head,tail;
5
6 void DEQUEUEinit(int maxN)
7 {
8 q=malloc(maxN*sizeof(Item));
9 if(q==NULL)
10 DEQUEUEerror();
11 head=0;
12 tail=0;
13 N=maxN;
14 }
15 void DEQUEUEerror(void)
16 {
17 printf("
空间可能已满或为空");
18 exit(1);
19 }
20 Item DEQUEUEheadget(void)
21 {
22 if(DEQUEUEisEmpty())
23 DEQUEUEerror();
24 Item temp=q[head];
25 head=(head+1)%N;
26 return temp;
27 }
28 Item DEQUEUEtailget(void)
29 {
30 if(DEQUEUEisEmpty())
31 DEQUEUEerror();
32 tail=(tail-1+N)%N;
33 return q[tail];
34 }
35 void DEQUEUEheadput(Item ch)
36 {
37 if(DEQUEUEisFull())
38 DEQUEUEerror();
39 head=(head-1+N)%N;
40 q[head]=ch;
41 }
42 void DEQUEUEtailput(Item ch)
43 {
44 if(DEQUEUEisFull())
45 DEQUEUEerror();
46 q[tail]=ch;
47 tail=(tail+1)%N;
48 }
49 int DEQUEUEisEmpty(void)
50 {
51 if(head==tail)
52 return 1;
53 return 0;
54 }
55 int DEQUEUEisFull(void)
56 {
57 if(((tail+1)%N)==head)
58 return 1;
59 return 0;
60 }
Item.h:
1 typedef char Item;
主程序 main.c：
1 #include <stdio.h>
2
3 int main(void)
4 {
5 int N;
6
7 printf("输入需要申请内存大小:");
8 if(scanf("%d", &N))
9 DEQUEUEinit(N);
10 else
11 DEQUEUEerror();
12 getchar();
13 printf("输入%d个字符",N);
14 printf("('+'从队头get '*'从队尾get '大写字母'"
15 "从队头put '小写字母'从队尾put):
");
16
17 while((N=getchar())!='
')
18 {
19 switch(N)
20 {
21 case '+':
22 putchar(DEQUEUEheadget());
23 break;
24 case '*':
25 putchar(DEQUEUEtailget());
26 break;
27 default:
28 if(N>64&&N<91)
29 DEQUEUEheadput(N);
30 else
31 DEQUEUEtailput(N);
32 }
33 }
34
35 return 0;
36 }