code: def constructIndexing(self):
          '''
          This helper function calculates the start and end index for each character in the BWT.  Basically, the information
          generated here is for quickly finding offsets.  This is run AFTER self.constructTotalCounts(...)
          '''
          #mark starts and ends of key elements
          self.startIndex = [None]*self.vcLen
          self.endIndex = [None]*self.vcLen
          pos = 0
          
          #go through the 1-mers
          for c in xrange(0, self.vcLen):
              #build start and end indexes
              self.startIndex[c] = pos
              pos += self.totalCounts[c]
              self.endIndex[c] = pof constructIndexing(self):
          '''
          This helper function calculates the start and end index for each character in the BWT.  Basically, the information
          generated here is for quickly finding offsets.  This is run AFTER self.constructTotalCounts(...)
          '''
          #mark starts and ends of key elements
          self.startIndex = [None]*self.vcLen
          self.endIndex = [None]*self.vcLen
          pos = 0
          
          #go through the 1-mers
          for c in xrange(0, self.vcLen):
              #build start and end indexes
              self.startIndex[c] = pos
              pos += self.totalCounts[c]
              self.endIndex[c] = pos
docs: This helper function calculates the start and end index for each character in the BWT.  Basically, the information
          generated here is for quickly finding offsets.  This is run AFTER self.constructTotalCounts(...)