编写一个算法，在基于单链表表示的待排序关键字序列上进行简单选择排序

#include <iostream>
#include <time.h>
#include <stdlib.h>
typedef struct node{
    int data;
    struct node *next;
}node,*pnode;

pnode buynode(int x)
{
    pnode tmp=(pnode) malloc(sizeof (node));
    tmp->data=x,tmp->next= nullptr;
    return tmp;
}

pnode buidlink()
{
    pnode head= buynode(-1);
    pnode tmp=head;
    for(int i=0;i<10;i++) tmp=tmp->next= buynode(rand()%20);
    return head;
}
void print(pnode head)
{
    while(head->next)
    {
        printf("%3d",head->next->data);
        head=head->next;
    }
    puts("");
}

void swap(pnode &n1,pnode &n2)
{
    int tmp=n1->data;
    n1->data=n2->data;
    n2->data=tmp;
}
void sort(pnode head)
{
    while(head->next)
    {
        pnode tmp=head->next;
        pnode record=tmp;
        while(tmp->next){
            if(record->data>tmp->next->data)record=tmp->next;
            tmp=tmp->next;
        }
        if(tmp!=head->next) swap(head->next,record);
        head=head->next;
    }
}
int main() {
    srand(time(nullptr));
    pnode h1=buidlink();
    print(h1);
    sort(h1);
    print(h1);
    return 0;
}