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 Rust (1.15.1) (judge verdict: Wrong Answer)

#![allow(non_snake_case)]

use std::io::prelude::*;
use std::io::stdin;
use std::str::FromStr;

fn main() {
    let mut S: Vec<char> = read::<String>().chars().collect();
    let T: Vec<char> = read::<String>().chars().collect();

    let mut ans = "UNRESTORABLE".to_string();

    if S.len() >= T.len() {
        for i in 0..S.len() - T.len() + 1 {
            if S[i..i + T.len()]
                .iter()
                .zip(T.iter())
                .all(|(s, t)| s == t || *s == '?')
            {
                for j in 0..T.len() {
                    S[i + j] = T[j];
                }
                ans = S.iter().map(|x| if *x == '?' { 'a' } else { *x }).collect();
                break;
            }
        }
    }

    println!("{}", ans);
}

#[allow(dead_code)]
fn read<T: FromStr>() -> T {
    let stdin = stdin();
    let token: String = stdin
        .lock()
        .bytes()
        .map(|b| b.unwrap() as char)
        .skip_while(|c| c.is_whitespace())
        .take_while(|c| !c.is_whitespace())
        .collect();
    token.parse().ok().unwrap()
}