is in your example abababa right answer aba or only a???
because a is 4 and aba is 3.

(aba)b(aba)

test №1: "abababa" ; correct answer: "a"
test №2: "abcde" ; correct answer: "abcde"

For "abcde" correct: a, b, c, d, e, ab, bc, cd, de, abc, bcd, cde, abcd, bcde, abcde



Edited by author 15.11.2010 10:11

why correct answer is "a" , in my opinion answer must be "ababa" cause prefix is like that 0 0 1 2 3 4 5