namespace std {
class ctype_base {
public:
using mask = see below;
static const mask space = 1 << 0;
static const mask print = 1 << 1;
static const mask cntrl = 1 << 2;
static const mask upper = 1 << 3;
static const mask lower = 1 << 4;
static const mask alpha = 1 << 5;
static const mask digit = 1 << 6;
static const mask punct = 1 << 7;
static const mask xdigit = 1 << 8;
static const mask blank = 1 << 9;
static const mask alnum = alpha | digit;
static const mask graph = alnum | punct;
};
}