// No.632 穴埋め門松列
package main

import (
	"fmt"
	"strings"
)

func main() {
	var c1, c2, c3 string
	fmt.Scan(&c1, &c2, &c3)

	ans := ""
	s1 := strings.Replace(c1+c2+c3, "?", "1", 1)
	if (s1[1] < s1[0] && s1[1] < s1[2]) || (s1[1] > s1[0] && s1[1] > s1[2]) {
		ans = ans + "1"
	}
	s4 := strings.Replace(c1+c2+c3, "?", "4", 1)
	if (s4[1] < s4[0] && s4[1] < s4[2]) || (s4[1] > s4[0] && s4[1] > s4[2]) {
		ans = ans + "4"
	}
	fmt.Println(ans)
}