数据结构：(栈)C语言简单实现

#include 
#include 
#include 

#define STACK_INIT_SIZE 100 // 存储空间初始分配量
#define STACKINCREMENT 10   // 存储空间分配增量

#define ok 1
#define error -1

typedef int SElemType;
typedef int Status;

typedef struct SqStack
{
  SElemType *base; // 栈底指针，栈构建之前和销毁之后都为NULL
  SElemType *top;  // 栈顶指针
  int stacksize;   // 当前已分配的存储空间，以元素为单位
}SqStack;

// 构造一个空栈
Status InitStack(SqStack *S)
{
  S->base = (SElemType *)malloc(STACK_INIT_SIZE * sizeof(SElemType));
  if(!S->base){ // 构造失败
    printf("构造失败n");
    return error;
  }
  S->top = S->base;
  S->stacksize = STACK_INIT_SIZE;
  printf("构造成功n");
  return ok;
}

// 销毁栈
Status DestroyStack(SqStack *S)
{
  S->top = NULL;
  S->stacksize = 0;
  free(S->base);
  return ok;
}

// 清空栈
Status ClearStack(SqStack *S)
{
  S->top = S->base;
  return ok;
}

// 判断栈是否为空
Status StackEmpty(SqStack *S)
{
  if(!S->base){
    printf("未创建栈n");
    return error;
  }
  if(S->base == S->top)
    printf("栈为空n");
  else{
    printf("栈不为空n");
  }
    return ok;
}

// 求栈的长度
Status StackLength(SqStack *S)
{
  return (S->top - S->base);
}

// 返回栈顶元素
Status GetTop(SqStack *S, SElemType *e)
{
  if(S->top == S->base)
    return error;
  *e = *(S->top);
  return ok; 
}

// 进栈
Status Push(SqStack *S,SElemType e)
{
  if(S->top - S->base >= S->stacksize){ // 栈满/栈剩余存储空间不够，追加存储空间

    // 注意这里使用的是 realloc()函数
    S->base = (SElemType *)realloc(S->base, (S->stacksize+STACKINCREMENT) * sizeof(SElemType));
    if(!S->base)
      return error;
    S->top = S->base + S->stacksize;
    S->stacksize = S->stacksize + STACKINCREMENT;
  }
  // *S->top++ = e; top和base指针一开始都为NULL，先让指针加一再插入元素
  S->top++;
  *S->top = e;
  return ok;
}

// 出栈，并用e返回其值
Status Pop(SqStack *S, SElemType *e)
{
  if(S->base == S->top)
    return error;
  *e = *S->top;
  S->top--;
  return ok;
}

// 从栈底到栈顶依次对栈中的每个元素调用函数visit()
Status StackTraverse(SqStack S, Status(* visit)(SElemType))
{
	while(S.top > S.base){
    S.base++;
    visit(*S.base);
  }
	printf("n");
	return ok;
}

// visit()函数 
Status visit(SElemType e)
{
	printf("%d ", e);
	return ok;
}

int main()
{
  int t;
  SElemType e;
  SqStack S;
   while (1)
  {
    printf("================================n");
    printf("               栈n");
    printf("================================n");
    printf("1:构造栈       2:进栈         3:出栈n");
    printf("4:销毁栈       5:清空栈       6:求栈长n");
    printf("7:判断栈是为空 8:返回栈顶元素 9:对栈调用visit()函数n");
    printf("--------------------------------n");
    printf("请选择:");
    scanf("%d", &t);
    switch (t)
    {
      case 1:
        InitStack(&S);
      break;
      case 2:
        printf("请输入要进栈的元素:");
        scanf("%d",&e);
        if(Push(&S,e) == 1)
        {
          printf("进栈成功n");
        }
      break;
      case 3:
        if(Pop(&S,&e) == 1){
          printf("取出的栈顶元素为:%dn",e);
        }else if(Pop(&S,&e) == -1){
          printf("空栈没有元素n");
        }
      break;
      case 4:
        if(DestroyStack(&S) == 1){
          printf("销毁栈成功n");
        }
      break;
      case 5:
        if(ClearStack(&S) == 1){
          printf("清空栈成功n");
        }
      break;
      case 6:
        printf("栈长为:%dn",StackLength(&S));
      break;
      case 7:
        StackEmpty(&S);
      break;
      case 8:
        if(GetTop(&S,&e) == 1){
          printf("栈顶元素为:%dn",e);
        }
      break;
      case 9:
        StackTraverse(S,visit);
      break;
    }
  }
  return 0;
}