update

Author: Blooverh

DataAndAlgoL/Chp3LinkedLists/Problem44.java

@@ -0,0 +1,41 @@
+package DataAndAlgoL.Chp3LinkedLists;
+/*
+ * Josephus Circle: N people have decided to elect a leader by arranging themselves in a circle
+ * and eleminenting every Mth person arounf the circle, closing ranks as each person drops out
+ * Find which person will be the last one remaining with rank 1
+ * 
+ * SOLUTION: Assume the input is a circular linked list with N nodes and each node has a number
+ * range 1 to N associated with it. Head node has number 1 as data.
+ */
+public class Problem44 {
+    public static void main(String[] args) {
+        
+    }
+
+    public ListNode getJosephusPosition(int N, int M){
+        ListNode p;
+        ListNode q;
+        //create circular linked list containing all the players
+        p.setData(1);
+
+        q=p;
+
+        for(int i=2; i<= N; i++){
+            p=p.getNext();
+            p.setData(i);
+        }
+
+        p.setNext(q); // Close the circular linked list by having the last node point to the first
+
+        for(int count=N; count >1; count--){
+            for(int i=0; i<M-1; i++){
+                p=p.getNext();
+                p.setNext(p.getNext().getNext());// remove the eliminated player from the list 
+            }
+        }
+
+        return p;
+
+        
+    }
+}

LeetCode/Grind169/LinkedLists/PalindromeLinkedList_234.java

@@ -60,4 +60,4 @@ public static boolean isPalindrome(ListNode head) {
 
         return true;
     }
-}
+}

LeetCode/Grind169/LinkedLists/RemoveNthNodeFromEndList_19.java

@@ -0,0 +1,35 @@
+package Grind169.LinkedLists;
+
+public class RemoveNthNodeFromEndList_19 {
+    public class ListNode {
+        int val;
+        ListNode next;
+        ListNode() {}
+        ListNode(int val) { this.val = val; }
+        ListNode(int val, ListNode next) { this.val = val; this.next = next; }
+    }
+
+    public static void main(String[] args) {
+        
+    }
+
+    //USE FLOYED CYCLE ALGORITHM
+    public ListNode removeNthFromEnd(ListNode head, int n) {
+        ListNode start = new ListNode(0);
+        ListNode slow = start, fast = start;
+        slow.next = head;
+    
+        //Move fast in front so that the gap between slow and fast becomes n
+        for(int i=1; i<=n+1; i++)   {
+            fast = fast.next;
+        }
+        //Move fast to the end, maintaining the gap
+        while(fast != null) {
+            slow = slow.next;
+            fast = fast.next;
+        }
+        //Skip the desired node
+        slow.next = slow.next.next;
+        return start.next;
+    }
+}