链表插入排序 lintcode

 链表插入排序

难度系数 容易 通过率 31%

 描述
 笔记

 数据

 评测

用插入排序对链表排序

您在真实的面试中是否遇到过这个题？ 

Yes

样例

Given 

1->3->2->0->null

,
return 

0->1->2->3->null

package tju.cs.bigdata.chc;

public class ListNode {
int val;
ListNode next;

ListNode(int val) {
this.val = val;
this.next = null;
}

public ListNode createList(String s){
ListNode res = new ListNode(-1);
String[] strings = s.split("->");
ListNode cur = res;
for(String st : strings){
if(!st.equals("null"))cur.next = new ListNode(Integer.parseInt(st));
cur = cur.next;
}

return res.next;
}
public void printList(ListNode l){
ListNode cur = l;
if(l == null)return;
while(cur != null){
System.out.print(cur.val + " ");
cur = cur.next;
}
}
}

package tju.cs.bigdata.chc;

public class InsertionSortList {
public ListNode insertionSortList(ListNode head) {
// write your code here
if(head == null || head.next == null){
return head;
}
ListNode res = new ListNode(-1);
ListNode cur = head;
ListNode curtmp = res;
while(cur != null){
curtmp = res;

while(curtmp.next != null && curtmp.next.val <= cur.val){
curtmp = curtmp.next;
}
//	            curtmp.printList(curtmp);
//	            cur.printList(cur);
ListNode l = cur.next;
cur.next = curtmp.next;
curtmp.next = cur;
cur = l;
//	            if(cur != null)cur.printList(cur);
//	            curtmp.printList(curtmp);
}
return res.next;

}
public static void main(String[] args){
String string = "1->3->2->0->null";
ListNode res = new ListNode(-1).createList(string);
res.printList(res);
InsertionSortList insertionSortList = new InsertionSortList();
ListNode res1 = insertionSortList.insertionSortList(res);
res1.printList(res1);
}
}