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 Haskell (GHC 7.10.3) (judge verdict: Wrong Answer)

{-# LANGUAGE OverloadedStrings #-}

import qualified Data.ByteString.Char8 as B
import Data.List

solve :: B.ByteString -> B.ByteString -> B.ByteString -> B.ByteString
solve s t acc
    | B.null s = "UNRESTORABLE"
    | lt /= ls = "UNRESTORABLE"
    | res = B.append (conv ds) $ B.append (B.reverse t) (conv acc)
    | otherwise = solve (B.tail s) t (B.cons (B.head s) acc)
    where
        res = and $ B.zipWith search ts t
        ts = B.take lt s
        ds = B.drop lt s
        lt = B.length t
        ls = B.length ts
        search a b
            | a == '?' = True
            | a == b = True
            | otherwise = False
        conv xs = B.foldl' (\acc x -> if x == '?' then B.cons 'a' acc else B.cons x acc) "" xs

main = do
    s <- B.getLine
    t <- B.getLine
    B.putStrLn $ solve (B.reverse s) (B.reverse t) ""