Page 98, Exercise 9 : failure function 
String: ababdababc

Failure  function for (aaaab) is:  -1  0  1  2  3
Failure  function for (ababaa) is:  -1  0  0  1  2  3
Failure  function for (abaabaab) is:  -1  0  0  1  1  2  3  4