Data structures implemented algorithm code - stacks and queues (a)

Stacks and queues

栈和队列是一种特殊的线性表。
从数据结构角度看：栈和队列也是线性表，其特点性在于栈和队列的基本操作是线性表操作的子集。它们是操作受限的线性表。
从数据类型角度看：它们是和线性表不相同的两类重要的抽象数据类型。

Defined stack

栈(Stack)是限定仅在表尾进行插入或删除操作的线性表。允许经行插入删除操作的表尾被称为栈顶，相应的表头被称为栈底。 
向栈中插入一个元素称为入栈(压栈)，从栈中删除一个元素称为出栈(退栈)。栈中无数据元素时称为空栈。
栈的特点：先进后出，后进先出(LIFO)。

And realize that stack

And similar linear form, there are two stacks stored representation namely: order and chain.

1, the chain storage stack: the stack is because the linear form, it is not a single linked list node structure lead sheets can be linear chain structure as a stack. Thus, you can use a single list of operations.
Such as:
single linked list initialization header as header stack;
single chain ListInsert (S, 1, e) as the stack operation of the stack Push;
single chain ListDeleteS, 1, * e) as the stack pop operations POP;
single interpolation head of the list, you can create a stack.

2, the stack stored in the order: for details see materials 46

//-----栈的顺序存储表示------
typedef struct {
    SElemType *base;
    SElemType *top;
    int stacksize;
}SqStack;

The basic operation of the stack

//------基本操作-----------
Status InitStack(SqStack *S){
	//构造一个空栈
	(*S).base =(SElemType *)malloc(STACK_INIT_SIZE*sizeof(SElemType));
	if(!(*S).base) exit(OVERFLOW);
	(*S).top =(*S).base;
	(*S).stacksize =STACK_INIT_SIZE;
	return OK;
}

//2
Status DestroyStack(SqStack *S){
	//销毁一个栈
	free( (*S).base);//释放表
	(*S).top =NULL;
	(*S).base =NULL;
	(*S).stacksize =0;
	return OK;
}

//3,
Status ClearStack(SqStack *S){
	//设置表为空
	(*S).top =(*S).base;//指向栈底
	return OK;
}

//4
Status StackEmpty(SqStack S){
	//是否为空
	if(S.top == S.base)
		return TRUE;
	else
		return FALSE;
}

//5
int StackLength(SqStack S){
	//返回栈的长度
	 return S.top-S.base;
}
//6
Status GetTop(SqStack S,SElemType *e){
	//如栈不空，返回栈顶元素
	if(S.top == S.base) 
		return ERROR;
	*e =*(S.top-1); //返回栈顶元素
	return OK;
}
//7
Status Push(SqStack *S,SElemType e){
	//入栈操作

	//判断栈满
	if( (*S).top-(*S).base >(*S).stacksize){
		(*S).base =(SElemType *)realloc((*S).base,((*S).stacksize+STACKINCREMENT)*sizeof(SElemType));
		if(!(*S).base) exit(OVERFLOW);

		(*S).top =(*S).base+(*S).stacksize;//重新定位栈顶指针
		(*S).stacksize+=STACKINCREMENT;
	}
	*( (*S).top )++ =e; //先插入，栈顶指针在+1
	return OK;
}
//8
Status Pop(SqStack *S,SElemType *e){
	//出栈操作

	//判断是否为空
	if((*S).top ==(*S).base) return ERROR;

	*e= *--(*S).top;//先栈顶指针-1，在取元素
	return OK;
}
//9
 Status StackTraverse(SqStack S,Status(*visit)(SElemType))
 { // 从栈底到栈顶依次对栈中每个元素调用函数visit()
   
   while(S.top>S.base)
     visit(*S.base++);
   printf("\n");
   return OK;
 }

Test code:

#include"ch2.h"
typedef int SElemType;
#include"Stack.c"

 Status visit(SElemType c)
 {
   printf("%d ",c);
   return OK;
 }

 //-----测试----
main(){
   int j;
   SqStack s;
   SElemType e;
   //
   printf("--------测试------------\n");
   printf("---初始化栈，并把1-6入栈---\n");
   if(InitStack(&s)==OK)
     for(j=1;j<=6;j++)
       Push(&s,j);
   printf("栈中元素依次为：");
   StackTraverse(s,visit);

   printf("---出栈操作---\n");
   Pop(&s,&e);
   printf("弹出的栈顶元素 e=%d\n",e);

   printf("栈是否空：%d(1:空 0:否)\n",StackEmpty(s));
   printf("---获取栈顶元素及栈的长度---\n");
   GetTop(s,&e);
   printf("栈顶元素 e=%d 栈的长度为%d\n",e,StackLength(s));

   printf("---清空栈---\n");
   ClearStack(&s);
   printf("清空栈后，栈是否空：%d(1:空 0:否)\n",StackEmpty(s));
   
   printf("---销毁栈---\n");
   DestroyStack(&s);
   printf("销毁栈后，s.top=%u s.base=%u s.stacksize=%d\n",s.top,s.base, s.stacksize);
}

Test results chart: