printRingInfo() {
    let result = '';

    for (var i = 0; i < this.rings.length; i++) {
      const ring = this.rings[i];
      result += ring.id + ';';
      result += ring.members.length + ';';
      result += ring.neighbours.length + ';';
      result += ring.isSpiro ? 'true;' : 'false;';
      result += ring.isFused ? 'true;' : 'false;';
      result += ring.isBridged ? 'true;' : 'false;';
      result += ring.rings.length + ';';
      result += '\n';
    }

    return result;
  }
Returns a string containing a semicolon and new-line separated list of ring properties: Id; Members Count; Neighbours Count; IsSpiro; IsFused; IsBridged; Ring Count (subrings of bridged rings)

@returns {String} A string as described in the method description.