import core.bitop;
import std.algorithm;
import std.ascii;
import std.bigint;
import std.conv;
import std.functional;
import std.math;
import std.numeric;
import std.range;
import std.stdio;
import std.string;
import std.random;
import std.typecons;
import std.container;

alias sread = () => readln.chomp();
ulong bignum = 1_000_000_007;
alias Pair = Tuple!(long, "number", long, "times");

T lread(T = long)()
{
    return readln.chomp.to!T();
}

T[] aryread(T = long)()
{
    return readln.split.to!(T[])();
}

void scan(TList...)(ref TList Args)
{
    auto line = readln.split();
    foreach (i, T; TList)
    {
        T val = line[i].to!(T);
        Args[i] = val;
    }
}

void main()
{
    auto s = sread();
    auto t = sread();
    auto dif = max(s.length - t.length, 0);
    foreach_reverse (i; 0 .. dif + 1)
    {
        auto parts = s[i .. t.length + i];
        if (parts.is_match(t))
        {
            ans_write(s, t, i);
            return;
        }
    }
    writeln("UNRESTORABLE");
}

bool is_match(T)(T a, T b)
{
    foreach (i, e; a)
    {
        if (!(e == b[i] || e == '?'))
            return false;
    }
    return true;
}

void ans_write(string s, string t, long p)
{
    auto s_before = s[0 .. p];
    auto s_after = s[p + t.length .. $];
    foreach (e; s_before ~ t ~ s_after)
    {
        if(e == '?')
            write('a');
        else
            e.write();
    }
    writeln();
}
