```go
package main

import (
	"fmt"
)

func main() {
	var u, v int64
	fmt.Scan(&u, &v)
	
	if u > v {
		fmt.Println(-1)
		return
	}
	
	diff := v - u
	if diff%2 != 0 {
		fmt.Println(-1)
		return
	}
	
	d := diff / 2
	
	if d == 0 {
		if u == 0 {
			fmt.Println(0)
		} else {
			fmt.Println(1)
			fmt.Println(u)
		}
		return
	}
	
	if (d & u) == 0 {
		fmt.Println(2)
		fmt.Println(d, d+u)
	} else {
		fmt.Println(3)
		fmt.Println(d, d, u)
	}
}
```