@@ -6,12 +6,13 @@ public class CircularLinkedList {
66 public Node tail ;
77 public int size = 0 ;
88
9+ // insert at Last
910 public void addLast (int data ) {
1011 Node node = new Node (data );
1112 if (head == null ) {
1213 head = node ;
1314 tail = node ;
14- node .next = node ;
15+ node .next = head ;
1516 } else {
1617 tail .next = node ;
1718 node .next = head ;
@@ -20,6 +21,85 @@ public void addLast(int data) {
2021 size ++;
2122 }
2223
24+ // add first
25+ public void addFirst (int data ) {
26+ Node node = new Node (data );
27+ if (head == null ) {
28+ head = node ;
29+ tail = node ;
30+ }
31+ node .next = head ;
32+ head = node ;
33+ size ++;
34+ }
35+ 36+ // insert at any
37+ public void add (int data , int index ) {
38+ if (index == 0 )
39+ addFirst (data );
40+ else if (index >= size - 1 )
41+ addLast (data );
42+ else {
43+ Node node = new Node (data );
44+ Node crr = head ;
45+ int i = 1 ;
46+ while (i ++ < index - 1 ) {
47+ crr = crr .next ;
48+ }
49+ node .next = crr .next ;
50+ crr .next = node ;
51+ size ++;
52+ }
53+ }
54+ 55+ // delete Last node
56+ public int deleteLast () {
57+ int data = tail .data ;
58+ Node n = head ;
59+ while (n .next .data != tail .data ) {
60+ n = n .next ;
61+ }
62+ size --;
63+ n .next = head ;
64+ tail = n ;
65+ return data ;
66+ }
67+ 68+ //delete First
69+ public int deleteFirst () {
70+ int data = head .data ;
71+ head = head .next ;
72+ tail .next = head ;
73+ size --;
74+ return data ;
75+ }
76+ 77+ // delete at any
78+ public int delete (int index ) {
79+ Node crr = head ;
80+ if (index == 0 )
81+ deleteFirst ();
82+ if (index == size - 1 )
83+ deleteLast ();
84+ int i = 1 ;
85+ while (i ++ < index )
86+ crr = crr .next ;
87+ int data = crr .next .data ;
88+ crr .next = crr .next .next ;
89+ size --;
90+ return data ;
91+ }
92+ 93+ // middle of the linked list
94+ public int middle () {
95+ Node slow = head , fast = head ;
96+ while (slow != null && fast .next != null ) {
97+ slow = slow .next ;
98+ fast = fast .next .next ;
99+ }
100+ return slow .data ;
101+ }
102+ 23103 //display the CircularLinkedList
24104 public void display () {
25105 Node n = head ;
@@ -39,5 +119,27 @@ public static void main(String[] args) {
39119 cll .addLast (50 );
40120 cll .display ();
41121 System .out .println (cll .size );
122+ 123+ cll .addFirst (1 );
124+ cll .display ();
125+ System .out .println (cll .size );
126+ 127+ cll .add (15 , 3 );
128+ cll .display ();
129+ System .out .println (cll .size );
130+ 131+ System .out .println ("Last Deleted Node => " + cll .deleteLast ());
132+ cll .display ();
133+ System .out .println (cll .size );
134+ 135+ System .out .println ("First Deleted Node => " + cll .deleteFirst ());
136+ cll .display ();
137+ System .out .println (cll .size );
138+ 139+ System .out .println ("Deleted Node => " + cll .delete (2 ));
140+ cll .display ();
141+ System .out .println (cll .size );
142+ 143+ System .out .println (cll .middle ());
42144 }
43145}
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