// Complete the freqQuery function below.
    static List<Integer> freqQuery(List<List<Integer>> queries) {

        List<Integer> q3Results = new ArrayList<>();
        Map<Integer,Integer> intElemFreqMap = new LinkedHashMap<>();

        for (int qIdx = 0 ; qIdx < queries.size() ; qIdx++) {
            assert(queries.get(qIdx).size() == 2);

            int opType = queries.get(qIdx).get(0);
            int opVal = queries.get(qIdx).get(1);
            
            // System.err.println("opType=>" + opType + "<");
            // System.err.println("opVal=>" + opVal + "<");

            switch(opType) {
                case 1:
                    intElemFreqMap.put(opVal, intElemFreqMap.getOrDefault(opVal, 0) + 1);
                    break;
                case 2:
                    if (intElemFreqMap.containsKey(opVal) && intElemFreqMap.get(opVal) >= 1) {
                        intElemFreqMap.put(opVal, intElemFreqMap.get(opVal) - 1);
                    }
                    break;
                case 3:
                    if (intElemFreqMap.containsValue(opVal)) {
                        q3Results.add(1);
                    } else {
                        q3Results.add(0);
                    }
                    break;
                default:
                    System.err.println("Unknown OpType=>" + opType + "<");
            }
        }
        
        return q3Results;
    }