Method divideArray

DivideArrayIntoEqualPairs.java:2–12

(int[] nums)

class Solution {
    public boolean divideArray(int[] nums) {
        HashSet<Integer> set = new HashSet<>();
        for(int num : nums){
            if(set.contains(num)){
                set.remove(num);
            }else{
                set.add(num);
            }
        }
        return (set.size()==0);   
    }
}