package main

import (
	"fmt"
	"strings"
)

func main() {
	a := input1()
	b := input2()
	n := len(a)
	result := []int{}
	for i := 0; i < n; i++ {
		if len(a[i]) != len(b[i]) {
			result = append(result, -1)
		}

		for _, letter := range a[i] {
			b[i] = strings.Replace(b[i], string(letter), "", 1)
		}
		result = append(result, len(b[i]))
		fmt.Println(a[i], b[i], len(b[i]))
	}

	fmt.Println(result)
}

func input1() []string {
	return []string{
		"a",
		"abb",
		"kj",
		"tea",
		"okk",
		"op",
		"xxxy1",
	}
}

func input2() []string {
	return []string{
		"bb",
		"abc",
		"jk",
		"toe",
		"koo",
		"mn",
		"xxxy2",
	}
}