/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		// your code goes here
		List<String> arr1 = new ArrayList<>();
		arr1.add("123");
		arr1.add("456");
 
		List<Integer> arr3 = new ArrayList<>();
		for (String s : arr1) {
			arr3.add(Integer.valueOf(s));
		}
 
		List<Integer> arr2 = arr3;
 
		System.out.println(arr2);
	}
}

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