how to add value to arraylist at index 0 code example

Example 1: ArrayList add(int index, E element) method in java

import java.util.ArrayList;
public class ArrayListAddMethodExample
{
   public static void main(String[] args)
   {
      // creating an empty ArrayList with initial capacity
      ArrayList<Integer> al = new ArrayList<Integer>(6);
      al.add(12);
      al.add(14);
      al.add(16);
      al.add(18);
      al.add(20);
      // adding element 15 at fourth position
      al.add(3, 15);
      for(Integer number : al)
      {
         System.out.println("Number: " + number);
      }
   }
}

Example 2: arraylist insert at position

//Insert a value by using arrayName.add(index, value)
//Will not remove current element at index. Will simply move all elements to
//the right.
import java.util.ArrayList;
public class main{
  public static void main(String[] args){
   ArrayList<Integer> list = new ArrayList<Integer>();
   	list.add(0);
    list.add(1);
    list.add(2);
    list.add(3);
    list.add(4);
    list.add(5);
    list.add(0, 100);
    
    //enhanced for loop will print all elements of the ArrayList
    for(int element : list){
    System.out.print(list + ", ");
      }
    //Expected output: "100, 0, 1, 2, 3, 4, 5, "
  }
  
}

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