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 Python (3.8.2) (judge verdict: Wrong Answer)

s = input()
t = input()
if len(s) < len(t):
    print("UNRESTORABLE")
    exit()
res = ""

s = s[::-1]
t = t[::-1]
n_s = len(s)
n_t = len(t)
i = 0
cnt = 0
flg = True
while i < n_s:
    if s[i] == '?':
        cnt += 1
        i += 1
    else:
        if s[i] == t[len(t)-1]: # tの先頭文字と同じ
            if n_t-1 < cnt:
                while n_t-1 != cnt:
                    res += 'a'
                    cnt -= 1
            if n_t-1 == cnt and flg:
                for j in range(n_t-1):
                    res += t[j]
                flg = False
            else:
                for j in range(cnt):
                    res += 'a'
        else:
            if n_t < cnt:
                for j in range(n_t):
                    res += t[j]
            else:
                for j in range(cnt):
                    res += 'a'
        res+= s[i]
        cnt = 0
        i += 1
if 0 < cnt:
    for i in range(cnt):
        res+='a'
res = res[::-1]
t = t[::-1]
if t in res:
    print(res)
else:
    print("UNRESTORABLE")