/*
 * GUESSTHE.c
 *
 *  Created on: Mar 6, 2014
 *      Author: Arpit Bhayani
 */

#include <stdio.h>
#include <stdlib.h>

#define DEBUG 0

long long int gcd(long long int a, long long int b) {
    if (b == 0)
        return a;
    return gcd(b, a % b);
}

long long int lcm(long long int a, long long int b) {

    if (a < b) {
        int t = a;
        a = b;
        b = t;
    }

    long long int lcm = (a * b) / gcd(a, b);
    return lcm;
}

int readline(char * str) {

    int i = 0;
    char ch;
    while ((ch = getchar()) != '\n') {
        str[i++] = ch;
    }
    str[i] = '\0';
    return i;
}

int main(int argc, char * argv[]) {

    long long int i, flag = 0;
    char ch;
    long long int number = 0;

    while (1) {

        i = 1;
        int array[21];

        for (i = 0; i < 21; i++) {
            array[i] = 0;
        }

        i = 1;
        ch = getchar();
        if (ch == '*') {
            break;
        } else if (ch == 'N') {
            array[i] = 1;
        }

        i++;
        number = 1;

        while ((ch = getchar()) != '\n') {
            if (ch == 'Y') {
                number = lcm(number, i);
            } else {
                array[i] = 1;
            }
            i++;
        }

        for (i = 1; i < 21; i++) {
            if (array[i] == 1) {
                if (number % i == 0) {
                    number = -1;
                    break;
                }
            }
        }

        printf("%lld\n", number);

    }
    return 0;
}