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Finding a loop in a linked List

Finding a loop in a linked List:-

public class LinkedListLoop {

 //Two pointers
 public Node loopCheck(Node head)
 {
  //fast pointer take two steps at a time
  Node fastptr=head;
  //slow pointer take one step at a time
  Node slowptr=head;
  
  if(head==null)
  {
   System.out.println("no loops empty list");
  }
  
  //Till any pointer becomes null
  while(slowptr!=null && fastptr!=null && fastptr.next!=null)
  {
   slowptr=slowptr.next;
   fastptr=fastptr.next.next;
   
   //if both pointers point to same node
   //possible only in loop list
   if(slowptr==fastptr)
   {
    System.out.println("loopfound");
    fastptr=head;
    while(fastptr.next!=slowptr)
    {
     fastptr=fastptr.next;
    }
     return fastptr;
   }
  }
  System.out.println("loop not found");
   return head;
 }
 
 public void makeCycle(Node head)
 {
  Node temp=head;
  while(temp.next.next!=null)
  {
   temp=temp.next;
  }
  temp.next=head.next.next;
 }
 
 
}

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Selection Sort in JAVA

What is selection sort?

It is a sorting technique that is based on the partitioning of array into two parts, sorted and unsorted.

The process is:-

1) Find minimum element in unsorted array.
2) Swap the element at the end of sorted array.

when i=0 we don't have any sorted array so element will be replaced from first element later the sorted array end will growas the index.

Steps:-


underline elements are sorted array, the length is increasing with each minimum element added at the end.minimum element11 1125122264 minimum element12 1112252264 minimum element22 1112222564 minimum element25 1112222564 minimum element64 1112222564
Program:-


package sorting;publicclassSelectionSort{//function to print arraypublicstaticvoidprint(int[] arr){for(int i=0;i<=arr.length-1;i++) System.out.print(" "+arr[i]); System.out.println(" ");}//function to swap elementspublicstaticint[]swap(int[] arr,int i,int j){int temp; temp=arr[i]; arr[i]=arr[j]; arr[j]=temp…