我已经颠倒了一个单链列表,并且交换了头和尾,但是在reverseList()
之后,输出仅显示列表的头。
/* Program to create a linked list and read numbers into it until the user
wants and print them using functions
Author: Shekhar Hazari
Created On: 20, January 2019 */
#include <stdio.h>
#include <stdlib.h>
struct node { int data; struct node *next; };
typedef node *list;
list head, tail;
list append(int d, list t);
void printList(list h);
void reverseList(list, list);
int main() {
char more = 'Y';
int dat;
head = (list)malloc(sizeof(node));
printf("Enter the first integer: ");
scanf("%d", &dat);
head->data = dat;
head->next = NULL;
tail = head;
printf("\nWant to add more data into the list? ");
scanf(" %c", &more);
while (more == 'y' || more == 'y') {
printf("Enter the integer to add to list: ");
scanf("%d", &dat);
tail = append(dat, tail);
printf("\nWant to add more data into the list? ");
scanf(" %c", &more);
}
printf("\nPrinting the list in the order it was entered: ");
printList(head);
reverseList(head, tail);
printf("\nPrinting the list after 'reverseList': ");
printList(head);
return 0;
}
// function to append integer to the list
list append(int d, list t) {
list temp;
temp = (list) malloc(sizeof(node));
temp->data = d;
t->next = temp;
temp->next = NULL;
t = temp;
return t;
}
// function to print the list
void printList(list h) {
list temp;
temp = h;
while (temp != NULL) {
printf("%d\t", temp->data);
temp = temp->next;
}
}
// function to reverse a singly linked list
void reverseList(list h, list t) {
list temp1, temp2;
temp1 = t; //temp2 = head;
while (temp1 != h) {
temp2 = h;
while (temp2->next != temp1)
temp2 = temp2->next;
temp1->next = temp2;
temp1 = temp2;
}
h = t;
t = temp1;
t->next = NULL;
return;
}
例如,我在列表中插入了5, 10, 15, 20, 25
,在reverseList()
之后,输出为5
。我哪里出错了?
答案 0 :(得分:0)
您不能反转列表,并保持head
和tail
指针不变。
reverseList
函数应获取指向head
和tail
的指针,并更新它们以指向反向列表的第一个和最后一个节点。此外,可以单次完成单链列表的反向操作。
此处是修改版本:
// function to reverse a singly linked list
void reverseList(list *headp, list *tailp) {
list temp, last, next;
*tailp = temp = *headp;
if (temp) {
while ((next = temp->next) != NULL) {
temp->next = last;
last = temp;
temp = next;
}
*headp = last;
}
}
以{p>
main