(d) A data pattern analyser is to be built that can detect and count up the number of occurrences of two- and three-letter same letter sequences in a sequence (e.g. (a,a) or (b,b,b)). The analyser should stop if it encounters * in the sequence and return the number of occurrences found up to that point in the form of a 2-tuple (#2LetterSequences, #3LetterSequences). A 3-letter sequence should only count as a 3-letter sequence, not an occurrence of two 2-letter sequences. No letter in the input sequence ever occurs more than 3 times in a row. So, for example: Input string (a,b,a,b,b,a,a,*) (x,x,x,y,y) (p,q,p,z,z,*) (*,a,a) (x,x,a,d,*, s,s,s,1) 2-letter sequences found 2 1 1 3-letter sequences found 0 1 0 0 0 0 1 Produce a formal statement of this problem, and then write an algorithm to solve the problem using a pseudo code style similar to the one shown in parts (a) to (c). State the bounds on the best- and worst-case performance of your algorithms using O, N and o appropriately to receive full marks