// No.486 3 Straight Win(3連勝)
package main

import (
	"fmt"
	"strings"
)

func main() {
	var s string
	fmt.Scan(&s)

	ew := strings.Index(s, "OOO") //east
	ww := strings.Index(s, "XXX") //west
	if ew == -1 && ww == -1 {
		fmt.Println("NA")
	} else if ww == -1 {
		fmt.Println("East")
	} else if ew == -1 {
		fmt.Println("West")
	} else {
		if ww > ew {
			fmt.Println("East")
		} else {
			fmt.Println("West")
		}
	}
}