双向链表的java实现

Posted 2020-09-05

  1 package structure;
  2 
  3 import java.util.Arrays;
  4 import java.util.Scanner;
  5 import static net.mindview.util.Print.*;
  6 
  7 /**
  8  * 双向链表的操作
  9  * @author Tom Tao
 10  *
 11  */
 12 class Node {
 13     public int value;
 14     public Node(int n) {
 15         this.value = n;
 16     }
 17     Node pre;
 18     Node next;
 19 }
 20 
 21 public class ReLinkedList {
 22     public static Node head;
 23     public static int nodeNum;
 24     
 25     /*初始化*/
 26     public static void init(int n[]) {
 27         head = new Node(n[0]);
 28         Node temp = null;
 29         head.pre = null;
 30         Node p = head;
 31         nodeNum ++;
 32         for(int i = 1 ; n[i] != -1 ; i ++) {
 33             nodeNum ++;
 34             temp = new Node(n[i]);
 35             p.next = temp;
 36             temp.pre = p;
 37             p = temp;
 38         }
 39         p.next = null;
 40     }
 41     
 42     /*打印*/
 43     public static void printList(Node h) {
 44         while(h != null) {
 45             printnb(h.value + " ");
 46             h = h.next;
 47         }
 48     }
 49     
 50     /*插入*/
 51     public static void insert(int index, int v) {
 52         Node ne = new Node(v);
 53         if(index == 0) {
 54             ne.next = head;
 55             ne.pre = null;
 56             head = ne;
 57             return;
 58         }
 59         Node temp = head;
 60         Node t = temp;
 61         for(int i = 0 ; i < index ; i ++) {
 62             t = temp;
 63             temp = temp.next;
 64         }
 65         if(index == nodeNum) {
 66             t.next = ne;
 67             ne.pre = t;
 68             ne.next = null;
 69             return;
 70         }
 71         ne.next = temp;
 72         ne.pre = t;
 73         temp.pre = ne;
 74         t.next = ne;
 75     }
 76     
 77     /*删除*/
 78     public static void delete(int index) {
 79         if(index == 0){
 80             head = head.next;
 81             head.pre = null;
 82             return;
 83         }
 84         Node temp = head;
 85         Node t = temp;
 86         for(int i = 0 ; i < index ; i ++) {
 87             t = temp;
 88             temp = temp.next;
 89         }
 90         if(index == nodeNum) {
 91             t.next = null;
 92             return;
 93         }
 94         t.next = temp.next;
 95         temp.next.pre = t;
 96     }
 97     
 98     /*查找*/
 99     public static int find(int index) {
100         Node temp = head;
101         for(int i = 0 ; i < index ; i ++) {
102             temp = temp.next;
103         }
104         return temp.value;
105     }
106     
107     /*test*/
108     public static void main(String[] args) {
109         Scanner sc = new Scanner(System.in);
110         print("please input the nums to init:");
111         int[] n = new int[100];
112         Arrays.fill(n, -1);
113         int val;
114         int count = 0;
115         while((val = sc.nextInt()) >= 0) {
116             n[count++] = val;
117         }
118         init(n);
119         while(true){
120             printList(head);
121             print("\nplease input the index and num to insert");
122             int index = sc.nextInt();
123             val = sc.nextInt();
124             insert(index, val);
125             printList(head);
126             print("\nplease input the index to delete");
127             index = sc.nextInt();
128             delete(index);
129             printList(head);
130             print("\nplease input the index to find");
131             index = sc.nextInt();
132             print(find(index));
133             print("----------------------------------------------------");
134         }
135     }
136 }