class VClock {

    public String returnVCString() {
        int mapSize = this.vc.size();
        int i = 0;
        StringBuilder vcString = new StringBuilder();
        vcString.append("{");
        for (Map.Entry<String, Long> clock : this.vc.entrySet()) {
            vcString.append("\"");
            vcString.append(clock.getKey());
            vcString.append("\":");
            vcString.append(clock.getValue());
            if (i < mapSize - 1) vcString.append(", ");
            i++;
        }
        vcString.append("}");
        return vcString.toString();
    }

    public  VClock();

}