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++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <bits/stdc++.h>
#define REP(i, n) for (int i = 0; i < n; i++)
#define REPR(i, n) for (int i = n; i >= 0; i--)
#define FOR(i, m, n) for (int i = m; i < n; i++)
#define ALL(v) v.begin(), v.end()
using namespace std;
typedef long long ll;
typedef long double ld;
int main()
{
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  string s,t;
  cin >> s >> t;
  int s_l = (int)s.size();
  int t_l = (int)t.size();
  if(s_l<t_l){
    cout << "UNRESTORABLE" << endl;
    return 0;
  }
  int p = -1;
  REPR(i,s_l-t_l){
    int cnt = 0;
    REP(j,t_l){
      if(s[i+j]!='?' && s[i+j]!=t[j]) break;
      else cnt++;
    }
    if(cnt==t_l){
      p = i;
      break;
    }
  }
  if(p==-1){
    cout << "UNRESTORABLE" << endl;
    return 0;
  }
  s.replace(p, p+t_l, t);
  int p2=0;
  int x;
  while((x = (int)s.find("?",p2))!=-1){
    s[x] = 'a';
    p2 += x;
  }
  cout << s << endl;
  return 0;
}