#include <cstdio>

bool g_students[17]{};

int main()
{
    int N;
    scanf("%d\n", &N);

    for (int i = 0; i < N; i++)
    {
        for (;;)
        {
            char c = getc(stdin);
            if (c == '\n') break;
            if ('a' <= c && c <= 'q')
            {
                int i = c - 'a';
                g_students[i] = true;
            }
        }
    }

    int sum = 0;
    char prev = 0;
    for (;;)
    {
        char c = getc(stdin);
        if ('a' <= c && c <= 'q') 
        {
            if (prev == c) continue;
            prev = c;

            if (!g_students[c - 'a']) continue;
            sum++;
        }
        else break;
    }

    printf("%d\n", sum - 1);

    return 0;   
}