Hack it

Alco is doing an ethical hacking course. He has to hack into his friend Ding's accounts. Alco already knows that Ding follows a certain kind of pattern when he sets his passwords. It is a pattern containing only +'s and -'s (+ represents increasing and - represents decreasing). The pattern's length is N. An array of numbers 1 2 3 .... N+1 is formed. Alco needs to find a permutation of the array