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`.
s=input()
t=input()
for i in range(len(t),len(s))[::-1]:
    if s[i]==t[-1] or s[i]=="?":
        if all(s[i-j]==t[-1-j] or s[i-j]=="?" for j in range(len(t))):
            s=s.replace("?","a")
            print(s[:i-len(t)]+t+s[i+1:])
            print(i)
            exit()
print("UNRESTORABLE")
s=input()
t=input()
for i in range(len(t)-1,len(s))[::-1]:
    if s[i]==t[-1] or s[i]=="?":
        if all(s[i-j]==t[-1-j] or s[i-j]=="?" for j in range(len(t))):
            s=s.replace("?","a")
            print(s[:i-len(t)+1]+t+s[i+1:])
            exit()
print("UNRESTORABLE")