Chef and Sign Sequences

Chef found a strange string yesterday - a string of signs s, where each sign is either a ', '=' or a '>'. Let N be the length of this string. Chef wants to insert N + 1 positive integers into this sequence and make it valid. A valid sequence is a sequence where every sign is preceded and followed by an integer, and the signs are correct. That is, if a sign 'a and followed by an integer b, then a s