package 剑指offer;

/**

* 实现链表的反转

* @author DELL

*分别通过循环和递归的方式进行反转操作

*/

public class LinkReverse {

//通过循环来实现反转

public T reverse(T t){

T pre=null;

while(t!=null){

T next=t.next;

t.next=pre;

pre=t;

t=next;

}

return pre;

}

//通过递归来实现链表的反转

public T reverse1(T t1){

if(t1.next==null)

return t1;

T next=t1.next;

T res=reverse1(next);

next.next=t1;

t1.next=null;

return res;

}

T pre=null;

public T reverse2(T t1){

T next=t1.next;

t1.next=pre;

if(next==null)

return t1;

pre=t1;

return reverse2(next);

}

public static void main(String[] args) {

LinkReverse lr=new LinkReverse();

T t1=new T(1);

T t=t1;

for(int i=2;i<9;i++){

t1.next=new T(i);

// System.out.println(t1.value);

t1=t1.next;

}

/*T tt=new T(2);

t1.next=tt;*/

T t2=lr.reverse2(t);

while(t2!=null){

System.out.println(t2.value);

t2=t2.next;

}

}

}