Checks to see if Cigar is well formed.
Checks to see if Cigar is well formed. We assume that it is well formed if the cigar lenmgth matches the read length.
Length of the read sequence.
Moves a single element in the cigar left by one position.
Moves a single element in the cigar left by one position.
Index of the element to move.
New cigar with this element moved left.