// #B
// yukicoder no.486 main.go
package main

import (
	"bufio"
	"fmt"
	"io"
	"os"
)

func solve(in io.Reader, out, err io.Writer) {
	str := []byte{}
	fmt.Fscan(in, &str)
	west, east := 0, 0
	for i := range str {
		if str[i] == 'O' {
			east++
			west = 0
		} else {
			west++
			east = 0
		}

		if east == 3 || west == 3 {
			if east > west {
				fmt.Fprintln(out, "East")
				return
			} else {
				fmt.Fprintln(out, "West")
				return
			}
		}
	}

	fmt.Fprintln(out, "NA")
}

func main() {
	br := bufio.NewReaderSize(os.Stdin, int(1e7))
	solve(br, os.Stdout, os.Stderr)
}