ListSum

package com.company;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;

public class ListSum
{
  public static void main(String[] args)
  {
    List<Integer> listOne = new ArrayList<>(Arrays.asList(1, 2, 3, 4, 5));

    int sum1 = listOne.stream().mapToInt(Integer::intValue).sum();
    int sum2 = 0;
    for (int i = 0; i < listOne.size(); i++) {
      sum2 += listOne.get(i);
    }
    System.out.println(sum1);
    System.out.println(sum2);

  }
}