package main

import (
	"fmt"
	"strings"
)

func main() {
	var s string
	fmt.Scan(&s)
	w := strings.Index(s, "OOO")
	l := strings.Index(s, "XXX")
	if w == -1 && l == -1 {
		fmt.Println("NA")
	} else if l == -1 {
		fmt.Println("East")
	} else if w == -1 {
		fmt.Println("West")
	} else if w < l {
		fmt.Println("East")
	} else {
		fmt.Println("West")
	}
}