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 Go (1.6) (judge verdict: Wrong Answer)

package main

import (
	"bufio"
	"fmt"
	"os"
	"strings"
)

var (
	sDash string
	t     string
	s     string
)

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Scan()
	sDash = scanner.Text()
	scanner.Scan()
	t = scanner.Text()

	//check if t can apply to sDash
	for i := len(sDash) - len(t); 0 <= i; i-- {
		k := 0
		match := false
		for j := i; j < i+len(t); j++ {
			fmt.Printf("i %d, j %d, k %d\n", i, j, k)
			if sDash[j] != '?' && sDash[j] != t[k] {
				match = false
				break
			}

			k++
			match = true
		}
		if match {
			s = sDash[:i] + t + sDash[(i+len(t)):]
			s = strings.Replace(s, "?", "a", -1)
			fmt.Println(s)
			return
		}

	}
	fmt.Println("UNRESTORABLE")
}