961. N-Repeated Element in Size 2N Array

class Solution {
    public int repeatedNTimes(int[] A) {
        int N = A.length/2;
        HashMap freq = new HashMap();
        for(int i = 0; i < A.length; i++){
              if(freq.get(A[i]) == null)
                freq.put(A[i],1);
            else if(freq.get(A[i]) != null){
                freq.put(A[i],freq.get(A[i]) + 1);  
                 if(freq.get(A[i]) == N) return A[i];

        }
        }
        return 0;
    }
}