Exercise 2.7\ Consider a postings intersection between this postings list, with skip pointers:\ and the following intermediate result postings list (which hence has no skip pointers):\

3,5,89,95,97,99,100,101

\ Trace through the postings intersection algorithm in Figure 210 (page 37).\ a. How often is a skip pointer followed (i.e.,

p_(1)

is advanced to

{:skip(p_(1)))

?\ b. How many postings comparisons will be made by this algorithm while intersect-\ ing the two lists?\ c. How many postings comparisons would be made if the postings lists are inter-\ sected without the use of skip pointers?

Exercise 2.7 [] Consider a postings intersection between this postings list, with skip pointers: and the following intermediate result postings list (which hence has no skip pointers): Trace through the postings intersection algorithm in Figure 210 (page 37). a. How often is a skip pointer followed (i.e., p1 is advanced to skip(p1)) ? b. How many postings comparisons will be made by this algorithm while intersecting the two lists? c. How many postings comparisons would be made if the postings lists are intersected without the use of skip pointers