栈、队列

写了点儿代码， 感觉指针真的不会

双栈共享空间：

#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <iostream>
const int Maxesize = 101;
typedef struct
{
    int data[Maxesize];
    int top1;
    int top2;
}SqDoubleStack, *Stack;
void Push(Stack &s, int e, int n)
{
    if(s->top1+1 == s->top2)
        printf("栈满"); 
    if(n == 1)
        s->data[++s->top1] = e;
    if(n == 2)
        s->data[--s->top2] = e;
//    printf("%d %d\n", s->top1, s->data[s->top1]);
//    printf("%d %d\n", s->top2, s->data[s->top2]);
}
void DeleteStack(Stack &s, int n, int *e)
{
    if(s->top1+1 == s->top2)
        printf("栈满"); 
    if(n == 1)
        e = &(s->data[s->top1--]);
    if(n == 2)
        e = &(s->data[s->top2--]);
    printf("%d\n", *e);
}
void DoubleStackInit(Stack &s/* == SqDoubleStack * &s*/)
{
    s=(SqDoubleStack *)malloc(sizeof(SqDoubleStack));   //先申请， 后使用： 
    s->top1 = -1;
    s->top2 = Maxesize;
    /*int i = 0;                  //ClearStack;
    while(i <  Maxesize)
    {
        s->data[i] = 0;
        i++;      
    }  */
    printf("%d %d\n", s->top1, s->top2);
}
int main()
{
    Stack Q;
    DoubleStackInit(Q);
    int c, n;
    scanf("%d%d", &n, &c);
    Push(Q, n, c);
    int e;
    scanf("%d", &n);
    DeleteStack(Q, n, &e);
    return 0;
}

 

队列知识点： 

循环队列判断条件满队列
　　rear: 头指针; front: 尾指针；
　　(rear+1)%Maxesize = front;
队列长度：
　　Length=(rear-front+Maxesize)%Maxesize;