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 Scala (2.11.7) (judge verdict: Accepted)

import java.io.{BufferedReader, InputStreamReader}

object Main extends App {

  def isMatch(arr:Array[Char], t:String, k:Int):Boolean = {
    for(i <- 0 until t.length) {
      if(t.charAt(i) != arr(i+k) && arr(i+k) != '?')
        return false
    }
    true
  }
  def construct(arr:Array[Char], t:String, k:Int):Unit = {
      for(i <- 0 until t.length) {
        arr(i+k) = t.charAt(i)
      }
  }

  val in = new BufferedReader(new InputStreamReader(System.in))
  val s, t = in.readLine

  val ans = {
    val arr = s.toCharArray
    var isMatched = false

    for(i <- s.length - t.length to 0 by -1) {
      if(isMatch(arr, t, i)) {
        if(!isMatched) {
          construct(arr, t, i)
          isMatched = true
        }
      }
    }

    if(isMatched) {
      for(i <- 0 until s.length) {
        if(arr(i) == '?') {
          arr(i) = 'a'
        }
      }
      arr.mkString
    }
    else "UNRESTORABLE"
  }

  println(ans)
}