package main

import "fmt"

func main() {
	var S string
	fmt.Scan(&S)
	s := []byte(S)
	w := 0
	e := 0
	for _, o := range s {
		if o == 'X' {
			e++
			if e == 3 {
				fmt.Println("West")
				return
			}
			w = 0
		} else if o == 'O' {
			w++
			if w == 3 {
				fmt.Println("East")
				return
			}
			e = 0
		}
	}
	fmt.Println("NA")
}