数据结构链表反转算法

数据结构链表反转算法

链表是数据结构中非常重要的一种结构，今天小编就在这分享一段“反转链表的源码”

**#include<stdio.h>
#include<malloc.h>
void createHeadNode();
void createNewNode(struct node *phead);
void showList(struct node *phead);
void showRevwesalList(struct node *phead2);
void findLastNode(struct node *phead);
void reversalList(struct node *phead);
struct node{
	int num;
	struct node *pnext;
};
struct node *phead = NULL;
struct node *phead2 = NULL;
int main(){
	int n = 0;
	createHeadNode();
	createNewNode(phead);
	findLastNode(phead);
	while (n < 5){
		reversalList(phead);
		n++;
	}
	showRevwesalList(phead2);
	return 0;
}
void createHeadNode(){
	phead = (struct node*)malloc(sizeof(struct node));
	phead->pnext = NULL;
}
void createNewNode(struct node *phead){
	struct node *top = phead;
	struct node *pnew = NULL;
	for (int i = 0; i < 5; i++){
		pnew = (struct node*)malloc(sizeof(struct node));
		if (i == 0){
			pnew->num = 1;
		}
		else if (i == 1){
			pnew->num = 2;
		}
		else if (i == 2){
			pnew->num = 3;
		}
		else if (i == 3){
			pnew->num = 4;
		}
		else if (i == 4){
			pnew->num = 5;
		}
		pnew->pnext = NULL;
		top->pnext = pnew;
		top = top->pnext;
	}
	showList(phead);
}
void showList(struct node *phead){
	struct node *top1 = phead->pnext;
	printf("反转前：\n");
	while (top1 != NULL){
		printf("%d  ", top1->num);
		top1 = top1->pnext;
	}
}
void findLastNode(struct node *phead){
	phead2 = phead->pnext;
	while (phead2 ->pnext!= NULL){
		phead2 = phead2->pnext;
	}
}
void showRevwesalList(struct node *phead2){
	printf("\n反转后：\n");
	while (phead2 != phead){
		printf("%d  ", phead2->num);
		phead2 = phead2->pnext;
	}
}
void reversalList(struct node *phead){
	struct node *top2 = phead;
	struct node *top3 = phead->pnext;
	while (top3->pnext!= NULL){
		top3 = top3->pnext;
		top2 = top2->pnext;	
	}
	top2->pnext = NULL;
	top3->pnext = top2;**
}

希望这段源码能够帮助正在学习链表的老铁们！！！！