题目

代码

package Chapter3; /** * * @author Crissu *原始链表哈哈哈哈哈哈 */ public class Three_Two {  public static void main(String[] args) {  // TODO Auto-generated method stub // 双链表 DlistChange(2, 3); // 单链表 SlistedChange(2, 3); } /** * 单链表换位 * 有头有尾链表 * @param pos1 * @param pos2 */ private static void SlistedChange(int pos1, int pos2) {  // TODO Auto-generated method stub Snode<Integer> Send = new Snode<>(null, null); Snode<Integer> S7 = new Snode<>(7, Send); Snode<Integer> S6 = new Snode<>(6, S7); Snode<Integer> S5 = new Snode<>(5, S6); Snode<Integer> S4 = new Snode<>(4, S5); Snode<Integer> S3 = new Snode<>(3, S4); Snode<Integer> S2 = new Snode<>(2, S3); Snode<Integer> S1 = new Snode<>(1, S2); Snode<Integer> Shead = new Snode<>(null, S1); // 交换前 System.out.println("单链表交换前："); Snode tmp = Shead.next; while (tmp.next != null) {  System.out.print(tmp.getValue()); tmp = tmp.next; } System.out.println(); // 交换 Snode tmp1 = Shead; Snode p1_pre = null, p1 = null, p2 = null; // 交换位置的节点 int index = -1; // 索引 while (tmp1.next != null) {  if (index == pos1 - 1) {  // System.out.printf("pos1-1:%d\n", pos1-1); p1_pre = tmp1; } if (index == pos1) {  // System.out.printf("pos1:%d\n", pos1); p1 = tmp1; } if (index == pos2) {  // System.out.printf("pos2:%d\n", pos2); p2 = tmp1; // 交换 p1.next = p2.next; p2.next = p1; p1_pre.next = p2; break; } index++; tmp1 = tmp1.next; } // 交换后 System.out.println("单链表交换后："); Snode tmp2 = Shead.next; while (tmp2.next != null) {  System.out.print(tmp2.getValue()); tmp2 = tmp2.next; } System.out.println(); } /** * 双链表换位 * 无头有尾链表 * @param pos1 * @param pos2 */ private static void DlistChange(int pos1, int pos2) {  // TODO Auto-generated method stub Dnode<Integer> Dlist = new Dnode<>(1, null, null); Dnode<Integer> D1 = new Dnode<>(2, null, null); Dlist.next = D1; D1.prev = Dlist; Dnode<Integer> D2 = new Dnode<>(3, null, null); D1.next = D2; D2.prev = D1; Dnode<Integer> D3 = new Dnode<>(4, null, null); D2.next = D3; D3.prev = D2; Dnode<Integer> D4 = new Dnode<>(5, null, null); D3.next = D4; D4.prev = D3; Dnode<Integer> D5 = new Dnode<>(6, null, null); D4.next = D5; D5.prev = D4; Dnode<Integer> D6 = new Dnode<>(7, null, null); D5.next = D6; D6.prev = D5; Dnode<Integer> end = new Dnode<>(null, null, null); D6.next = end; end.prev = D6; Dnode tmp = Dlist; Dnode tmp2 = Dlist; Dnode tmp3 = Dlist; System.out.println("双链表交换前："); while (tmp2.next != null) {  System.out.print(tmp2.getValue()); tmp2 = tmp2.next; } System.out.println(); // 交换 int index = 0; Dnode<Integer> p1 = new Dnode<>(null, null, null); Dnode<Integer> p2 = new Dnode<>(null, null, null); while (tmp.next != null) {  if (index == pos1) {  p1 = tmp; } if (index == pos2) {  p2 = tmp; // 开始交换 p1.prev.next = p2; p1.next = p2.next; p2.next.prev = p1; p2.next = p1; p2.prev = p1.prev; p1.prev = p2; break; } index++; tmp = tmp.next; } // System.out.printf("带交换的数1：%d\n", p1.getValue()); // System.out.printf("带交换的数2：%d\n", p2.getValue()); System.out.println("双链表交换后："); while (tmp3.next != null) {  System.out.print(tmp3.getValue()); tmp3 = tmp3.next; } System.out.println(); } } /** * 双链表节点 * * @author Administrator * */ class Dnode<AnyType> {  private AnyType value; public Dnode prev; public Dnode next; public Dnode(AnyType v, Dnode p, Dnode n) {  value = v; prev = p; next = n; } public AnyType getValue() {  return this.value; } } /** * 单链表节点 * * @author Administrator * * @param <AnyType> */ class Snode<AnyType> {  private AnyType value; public Snode next; public Snode(AnyType v, Snode n) {  value = v; next = n; } public AnyType getValue() {  return this.value; } } 

结果