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 C# (Mono 4.6.2.0) (judge verdict: Wrong Answer)

using System;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Linq.Expressions;
using System.Text;
class Simple{
    string S, T;
    void Solve(){
        //input
        S = io.String;
        T = io.String;
        //cal
        if (T.Length > S.Length) {
            Console.WriteLine("UNRESTORABLE");
            return;
        }
        var X = S.Select(c => c == '?' ? 'a' : c).ToArray();
        for(int i = 0; i < S.Length - T.Length + 1; ++i){
            var f = true;
            for(int j = 0; j < T.Length; ++j){
                if(S[i + j] == '?' || S[i + j] == T[j]){
                    //
                }
                else{
                    f = false;
                    break;
                }
            }
            if(f){
                for(int j = 0; j < T.Length; ++j) if(S[i + j] == '?' || S[i + j] == T[j]) X[i + j] = T[j];
                //ret
                Console.WriteLine(new string(X));
                return;
            }
        }
        //ret
        Console.WriteLine("UNRESTORABLE");
    }
    SimpleIO io = new SimpleIO();
    public static void Main(string[] args) { new Simple().Stream(); }
    void Stream(){
        Solve();
        io.writeFlush();
    }
}
class SimpleIO{
    string[] nextBuffer;
    int BufferCnt;
    char[] cs = new char[]{' '};
    StreamWriter sw = new StreamWriter(Console.OpenStandardOutput()){AutoFlush = false};
    public SimpleIO(){
        nextBuffer = new string[0];
        BufferCnt = 0;
        Console.SetOut(sw);
    }
    public string Next(){
        if(BufferCnt < nextBuffer.Length) return nextBuffer[BufferCnt++];
        string st = Console.ReadLine();
        while(st == "") st = Console.ReadLine();
        nextBuffer = st.Split(cs, StringSplitOptions.RemoveEmptyEntries);
        BufferCnt = 0;
        return nextBuffer[BufferCnt++];
    }
    public string String => Next();
    public char Char => char.Parse(String);
    public int Int => int.Parse(String);
    public long Long => long.Parse(String);
    public double Double => double.Parse(String);
    public void writeFlush() { Console.Out.Flush(); }
}