huiwen.c

回文问题

#include<stdio.h>
#define maxsize 50
typedef char DataType;

typedef struct 
{
	DataType queue[maxsize];
	int rear;
	int front;
	int count;
}SeqCQueue;

void QueueInitiate(SeqCQueue *Q)
{
	Q->rear=0;
	Q->front=0;
	Q->count=0;
}

int QueueNotEmpty(SeqCQueue *Q)
{
	if(Q->count<=0)
		return 0;
	else return 1;
}

int QueueAppend(SeqCQueue *Q,DataType x)         /*勿忘记写上DataType！x前莫打星号！*/
{
	if(Q->rear==Q->front&&Q->count!=0)          
	{printf("It's full.\n");return 0;}
	else
	{
		Q->queue[Q->rear]=x;
		Q->rear=(Q->rear+1)%maxsize;
		Q->count++;
		return 1;
	}
}

int QueueDelete(SeqCQueue *Q,DataType *x)
{
	if(Q->count==0)
	{printf("It's empty.\n");return 0;}
	else
	{
		*x=Q->queue[Q->front];
	     Q->front=(Q->front+1)%maxsize;
	     Q-> count--;
		return 1;
	}
}
	
int QueueGet(SeqCQueue *Q,DataType *x)
{                                                                  /*只能取队头的元素！*/
	if(Q->count==0)
	{printf("It's empty.\n");return 0;}
	else 
	{
		*x=Q->queue[Q->front];
		return 0;
	}
}

typedef struct 
{
	DataType stack[maxsize];
	int top;
}SeqStack;

void StackInitiate(SeqStack *S)    /*原未写上SeqStack!形参也要写上类型！*/
{
	S->top=0;
}

int StackNotEmpty(SeqStack *S)
{
	if(S->top==0)         /*书上写的是S.top<=0*/
		return 0;
	else return 1;
}

int StackPush(SeqStack *S,DataType x)
{
	if(S->top>=maxsize)      /*最后一个数的编号是maxsize-1,当=maxsize时就已经满足了*/
	{
		printf("It's full.\n");
		return 0;
	}
	else 
	{S->stack[S->top]=x;         /*应该写成S->top，不能直接写top,在此子函数中没有定义top*/
		S->top++;                   /*原错同上*/
	      return 1;
	}
}

int StackPop(SeqStack *S,DataType *x)
{
	if(S->top<=0)
	{
		printf("It's empty.\n");
		return 0;
	}
	else
	{
		S->top--;
		*x=S->stack[S->top];
		return 1;
	}
	
}

int StackTop(SeqStack *S,DataType *x)     
{
	if(S->top<=0)
	{
		printf("It's empty.\n");
		return 0;
	}
	else
	{
		*x=S->stack[S->top-1];
		return 1;
	}
}

void HuiWen(char str[])
{
	SeqCQueue myqueue;
	SeqStack mystack;
	int i;char x,y;int flag=1;
	QueueInitiate(&myqueue);
	StackInitiate(&mystack);
	for(i=0;str[i]!='\0';i++)
	{
		if(!QueueAppend(&myqueue,str[i]))
		{system("pause");exit(0);}
		if(!StackPush(&mystack,str[i]))
		{system("pause");exit(0);}
	}
	for(i=0;str[i]!='\0';i++)
	{
		if(!(QueueDelete(&myqueue,&x)&&StackPop(&mystack,&y)&&x==y))
		flag=0;
	}
	if(flag)
		printf("%s is huiwen.\n",str);
	if(!flag)
		printf("%s is NOT huiwen.\n",str);
}


void main()
{
	char a[]="abcdedcba";
	char b[]="abcdedcab";
	HuiWen(a);
	HuiWen(b);
}