读入挂输出挂

template <class T>inline bool scan_d(T &ret){    char c;    int sgn;    if (c = getchar(), c == EOF)    {        return 0; //EOF    }    while (c != '-' && (c < '0' || c > '9'))    {        c = getchar();    }    sgn = (c == '-') ? -1 : 1;    ret = (c == '-') ? 0 : (c - '0');    while (c = getchar(), c >= '0' && c <= '9')    {        ret = ret * 10 + (c - '0');    }    ret *= sgn;    return 1;}void Out(ll a){    //  输出外挂    if (a < 0)    {        putchar('-');        a = -a;    }    if (a >= 10)    {       Out(a / 10);    }    putchar(a % 10 + '0');}