队列例程

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124

#include "stdlib.h"

#define Element int

struct ;
typedef struct *Queue;

int IsEmpty(Queue Q);
int Isfull(Queue Q);
Queue creat(int Maxsize);
void DisposeQueue(Queue Q);
void MakeEmpty(Queue Q);
void EnQueue(Element X,Queue Q);
void DeQueue(Queue Q);//出队
Element ReturnQueue(Queue Q);//返回队首元素

#define Minsize (5)

struct
{
int capacity;//上限,可由Maxsize输入控制,或利用define.
int front;//队首
int rear;//队尾
int size;
Element *Array;
};

int IsEmpty(Queue Q)
{
return Q->size==0;//if Q->size==0, return it
}

int IsFull(Queue Q)
{
if(Q->size==Q->capacity)
return 0;
else
return 1;
}

Queue creat(int Maxsize)
{
Queue Q;
Q=(Queue)malloc(sizeof(struct QueueRecord));
MakeEmpty(Q);
Q->capacity=Maxsize;
Q->Array=(Element*)malloc(sizeof(Element)*Maxsize);
return Q;
}

void DisposeQueue(Queue Q)
{
if(!IsEmpty(Q))
{
free(Q->Array);
free(Q);
}
}

void MakeEmpty(Queue Q)
{
Q->size=0;
Q->front=1;
Q->rear=0;
}

int Succ(int Value,Queue Q)
{
if(Value==Q->capacity)//若队尾过界,重新置为0,进行入队
Value=0;
else
Value++;
return Value;//上一个if条件句
}

void EnQueue(Element X,Queue Q)
{
if(IsFull(Q)==0)//若队列满(若循环队列,此行需改变)
printf("Queue has been full!n");
else
{
Q->size++;
Q->rear=Succ(Q->rear,Q);//并非构建循环队列 只是为了防止rear或front超出数组范围
Q->Array[Q->rear]=X;
}
}

void DeQueue(Queue Q)
{
if(IsFull(Q)==0)
printf("Queue has been full!n");
else
{
Q->size--;
Q->front=Succ(Q->front,Q);
}
}

Element ReturnQueue(Queue Q)
{
return Q->Array[Q->front];
}

int main()
{
Queue Q;
int n;
scanf("%d",&n);
Q=creat(n);
int x;
int i;
int temp;
EnQueue(3,Q);
EnQueue(4,Q);
temp=ReturnQueue(Q);
printf("%dn",temp);
DeQueue(Q);
temp=ReturnQueue(Q);
printf("%dn",temp);
return 0;

}
c