单链表排序之选择排序

对单链表进行选择排序，选择排序算是比较直观的排序算法，利用C语言实现

#include <stdio.h>
struct ListNode{
	int val;
	struct ListNode *next;
};
struct ListNode *create_list(){
	int i;
	struct ListNode *head=(struct ListNode*)malloc(sizeof(struct ListNode));
	struct ListNode *p;
	head->next=NULL;
	scanf("%d",&i);
	while(i!=-1){//输入-1结束 
		p=(struct ListNode *)malloc(sizeof(struct ListNode));
		p->val=i;
		p->next=head->next;
		head->next=p;
		scanf("%d",&i);		
	}
	return head;	
}
void print_list(struct ListNode *head){
	struct ListNode *p=head->next;
	while(p){
		printf("%d ",p->val);
		p=p->next;
	}
	printf("\n");
} 
void selectSort(struct ListNode *head){
	struct ListNode *p,*q,*min;
	int temp;
	if(head==NULL || head->next==NULL || head->next->next==NULL){
		exit(-1); 
	} 
	p=head->next;
	q=p->next;
	min=p;
	while(p){
		q=p->next;
		min=p;
		while(q){
			if(q->val < min->val){
				min=q;
			}
			q=q->next;		
		}
		temp=p->val;
		p->val=min->val;
		min->val=temp;	
		p=p->next;
	}
}

int main(){
	struct ListNode *head=create_list();
	printf("before sort:\n");
	print_list(head);
	printf("select sorting...\n");
	selectSort(head);
	printf("output after sort:\n");
	print_list(head);
	return 0;
}