Algorithm 2 outputs a critical factorization
for a given input partial word w with p'(w) > 1 and with one hole of length at
least two when such a factorization exists, and outputs "no critical
factorization exists"
otherwise.
**Note: This program uses the special character '^'
to represent a hole (do not know symbol) in a partial word. Only one hole ('^') is
allowed.