Problem:
Score : 300 points

Problem Statement

E869120 found a chest which is likely to contain treasure.

However, the chest is locked. In order to open it, he needs to enter a string S consisting of lowercase English letters.

He also found a string S', which turns out to be the string S with some of its letters (possibly all or none) replaced with ?.

One more thing he found is a sheet of paper with the following facts written on it:

Condition 1: The string S contains a string T as a contiguous substring.

Condition 2: S is the lexicographically smallest string among the ones that satisfy Condition 1.

Print the string S.

If such a string does not exist, print UNRESTORABLE.

Constraints

1 \leq |S'|, |T| \leq 50

S' consists of lowercase English letters and ?.

T consists of lowercase English letters.

Input

Input is given from Standard Input in the following format:

S
T'

Output

Print the string S.

If such a string does not exist, print UNRESTORABLE instead.

Sample Input 1

?tc????
coder

Sample Output 1

atcoder

There are 26 strings that satisfy Condition 1: atcoder, btcoder, ctcoder,..., ztcoder.
Among them, the lexicographically smallest is atcoder, so we can say S = atcoder.

Sample Input 2

??p??d??
abc

Sample Output 2

UNRESTORABLE

There is no string that satisfies Condition 1, so the string S does not exist.

Solution in Common Lisp (SBCL 1.1.14) (judge verdict: Accepted)

(let* ((n (read-line))
       (s (read-line))
       (a nil))
  (defun f-equal (a b)
    (reduce (lambda (x y) (and x y))
            (map 'list (lambda (x y) (if (char= #\? x)
                                               t (char= x y))) a b)))
  (setf a (position t (loop :for k :from 0 :to (- (length n) (length s)) :collect (f-equal (subseq n k (+ k (length s))) s)) :from-end t))
  (if a
      (princ (map 'string (lambda (k) (if (char= #\? k) #\a k)) (concatenate 'string (subseq n 0 a) s (subseq n (+ a (length s)))) ))
      (princ "UNRESTORABLE")))