Scala Bitsets are sets of non-negative integers which are represented as variable-size arrays of bits packed into 64-bit words. The
addString(sb: mutable.StringBuilder, start: String, sep: String, end: String) method is utilised to appends all elements of this bitset to a string builder using start, end, and separator strings.
Method Definition: def addString()
Return Type: It returns the string builder b to which elements were appended.
BitSet(11, 22, 33, 44)