code: func (sba *sparseBitArray) ClearBit(k uint64) error {
  	index, position := getIndexAndRemainder(k)
  	i := sba.indices.get(index)
  	if i == -1 {
  		return nil
  	}
  
  	sba.blocks[i] = sba.blocks[i].remove(position)
  	if sba.blocks[i] == 0 {
  		sba.blocks.deleteAtIndex(i)
  		sba.indices.deleteAtIndex(i)
  	}
  
  	return nil
  }
docs: // ClearBit clears the bit at the given position.