C.问题中的双端队列结构

时间:2015-02-24 19:16:29

标签: c struct deque

我试图创建出列结构来插入/删除第一个节点,插入/删除最后一个节点。我已经在一个.c文件中写了所有内容并且它工作得很好,但是当我尝试从中创建一个项目文件时(3个文件:main,header,functions),它只是不起作用。制作项目后遇到的第一个问题:打印无限次出列(函数void printDeque(deque *d))。

这是工作的单文件代码:

#include<stdio.h>
#include<stdlib.h>

typedef struct dequeNode *link;
struct dequeNode{
    int data;
    link next;
};


typedef struct{
    link front;
    link rear;
}deque;


void initDeque(deque *d){ //Create new deque
    d->front=NULL;
    d->rear=NULL;
}


int isEmpty(deque *d){  //Function to find, if deque is empty
    if((d->front)==NULL){
        return 0;
    }else{
        return 1;
    }
}


void putFront(deque *d,int x){ //Function to insert data in front of deque
    link node=(link)malloc(sizeof(struct dequeNode));
    node->data=x;
    node->next=NULL;
    if(isEmpty(d)){
        node->next=d->front;
        d->front=node;
    }else{
        d->front=node;
        d->rear=node;
    }
}


void putRear(deque *d,int x){ //Function to insert data in rear of deque
    link node=(link)malloc(sizeof(struct dequeNode));
    node->data=x;
    node->next=NULL;
    if(isEmpty(d)){
        d->rear->next=node;
        d->rear=node;
    }else{
        d->front=node;
        d->rear=node;
    }
}


int getFront(deque *d){ //Delete first node of deque
    link node=d->front;
    int x=node->data;
    if((d->front)==(d->rear)){
        d->front=NULL;
        d->rear=NULL;
    }else{
        d->front=node->next;
    }
    free(node);
    return x;
}


int getRear(deque *d){ //Delete last node of deque
    link node=d->front;
    link tr=d->rear;
    int x=tr->data;
    if(node==tr){
        d->front=NULL;
        d->rear=NULL;
    }else{
        while((node->next)!=tr){
            node=node->next;
        }
        d->rear=node;
    node->next=NULL;
    }
    free(tr);
    return x;
}


void printDeque(deque *d){ //Print out deque to console
    link node=d->front;
    while(node!=NULL){
        printf("%d ",node->data);
        node=node->next;
    }
}


void main(){
    int x;
    deque *d;
    d=(deque*)malloc(sizeof(deque));
    initDeque(d);
    putFront(d,10);
    putFront(d,20);
    putRear(d,30);
    putFront(d,40);
    putRear(d,50);
    putFront(d,60);
    printf("\n");
    printDeque(d);
    if(isEmpty(d))
        x=getFront(d);
    printf("\n");
    printDeque(d);
    if(isEmpty(d))
        x=getRear(d);
    printf("\n");
    printDeque(d);
    if(isEmpty(d))
    x=getFront(d);
    printf("\n");
    printDeque(d);
}

这里有三个文件来制作一个项目:

main.c

#include<stdio.h>
#include<stdlib.h>
#include"deque.h"

void main(){
    int x;
    deque *d;
    d=(deque*)malloc(sizeof(deque));
    initDeque(d);
    putFront(d,10);
    putFront(d,20);
    printDeque(d);
    putRear(d,30);
    putFront(d,40);
    putRear(d,50);
    putFront(d,60);
    printf("\n");
    printDeque(d);
    if(isEmpty(d))
        x=getFront(d);
    printf("\n");
    printDeque(d);
    if(isEmpty(d))
        x=getRear(d);
    printf("\n");
    printDeque(d);
    if(isEmpty(d))
    x=getFront(d);
    printf("\n");
    printDeque(d);
}

头文件(deque.h):

#ifndef deque_H
#define deque_H
typedef struct dequeNode *link;
struct dequeNode{
    int data;
    link next;
};


typedef struct{
    link front;
    link rear;
}deque;



void initDeque(deque*);
int isEmpty(deque*);
void putFront(deque*,int);
void putRear(deque*,int);
int getFront(deque*);
int getRear(deque*);
void printDeque(deque*);


#endif

和函数文件(functions.c):

#include<stdio.h>
#include<stdlib.h>
#include"deque.h"



void initDeque(deque *d){ //Create new deque
    d->front=NULL;
    d->rear=NULL;
}


int isEmpty(deque *d){  //Function to find, if deque is empty
    if((d->front)==NULL){
        return 0;
    }else{
        return 1;
    }
}


void putFront(deque *d,int x){ //Function to insert data in front of deque
    link node=(link)malloc(sizeof(struct dequeNode));
    node->data=x;
    node->next=NULL;
    if(isEmpty(d)){
        node->next=d->front;
        d->front=node;
    }else{
        d->front=node;
        d->rear=node;
    }
}


void putRear(deque *d,int x){ //Function to insert data in rear of deque
    link node=(link)malloc(sizeof(struct dequeNode));
    node->data=x;
    node->next=NULL;
    if(isEmpty(d)){
        d->rear->next=node;
        d->rear=node;
    }else{
        d->front=node;
        d->rear=node;
    }
}


int getFront(deque *d){ //Delete first node of deque
    link node=d->front;
    int x=node->data;
    if((d->front)==(d->rear)){
        d->front=NULL;
        d->rear=NULL;
    }else{
        d->front=node->next;
    }
    free(node);
    return x;
}


int getRear(deque *d){ //Delete last node of deque
    link node=d->front;
    link tr=d->rear;
    int x=tr->data;
    if(node==tr){
        d->front=NULL;
        d->rear=NULL;
    }else{
        while((node->next)!=tr){
            node=node->next;
        }
        d->rear=node;
    node->next=NULL;
    }
    free(tr);
    return x;
}


void printDeque(deque *d){ //Print out deque to console
    link node=d->front;
    while(node!=NULL){
        printf("%d ",node->data);
        node=node->next;
    }
}

第二个问题:我在deque *d; d=(deque*)malloc(sizeof(deque));中创建了第一个节点int main,但是有可能创建它,比如说void initDeque()吗?

1 个答案:

答案 0 :(得分:0)

你遇到的第一个问题 - isEmpty()函数出错。如果为NULL,则应返回true,如果不为NULL - 则应返回false。

UPD。为了保持其余代码不变,您可以将isEmpty重命名为isNotEmpty(假设为isedev)。此外,值得添加检查此函数中“d”指针是否等于NULL:

//Function to find, if deque is not empty
int isNotEmpty(deque *d)
{
    if (!d || !d->front)
        return 0;
    return 1;
}