src/main/java/com/fishercoder/solutions/_561.java

package com.fishercoder.solutions;

import java.util.Arrays;

public class _561 {

    public static class Solution1 {
        public int arrayPairSum(int[] nums) {
            Arrays.sort(nums);
            int sum = 0;
            for (int i = 0; i < nums.length; i += 2) {
                sum += nums[i];
            }
            return sum;
        }
    }

}