bool read(){
    if(scanf("%d", &q) != 1)
        return 0;
    while (getchar() != '\n');
    char c;
    forn(i, q){
        b[i] = "";
        do{
            c = getchar();
            if (c != '\n')
                b[i] += c;
        } while (c != '\n');
    }
    scanf("%d", &m);
    while (getchar()!='\n');
    int lst = 0;
    s = "";
    forn(i, m){
        t = "";
        do{
            c = getchar();
            if (c != 10)
                t += c;
        } while (c != 10);

        forn(j, sz(t))
            pos[lst++] = mp(i + 1, j + 1);

        lst++;
        s += t;
        s += (char)(10);
    }
    n = sz(s);
    return 1;
}