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

int factorial(int num)
{
    return num == 1 ? 1 : num * factorial(num - 1);
}


int main()
{
    int wordlength;
    scanf("%d\n", &wordlength);
    char* letters = (char*)malloc(sizeof(char) * (wordlength + 1));
    
    scanf("%s", letters);
    
    //fputs(letters, stdout);
    int db = 0;
    for (int i = 0; i < wordlength; i++)
    {
        if (letters[i] == '_')
        {
            db++;
        }
    }
    int sol = 1;
    for (int i = 26 - wordlength + 1; i <= 26 - (wordlength - db); i++) {
        sol *= i;
    }
    printf("%d", sol);


    free(letters);

    return 0;
}