// No.1941 CHECKER×CHECKER(1)
package main

import (
	"fmt"
	"strings"
)

func main() {
	var s1, s2, s3 string
	fmt.Scan(&s1, &s2, &s3)

	ans := "Yes"
	ss := strings.Join([]string{s1, s2, s3}, "")
	for i := 1; i < len(ss); i++ {
		if ss[i] == ss[i-1] {
			ans = "No"
		}
	}
	fmt.Println(ans)
}