#include <ctype.h>

int isspace(int c) { return c == ' ' || c == '\t' || c == '\n' || c == '\12'; }

int isdigit(int c) { return c >= '0' && c <= '9'; }

int isalpha(int c) { return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z'); }

int isupper(int c) { return (c >= 'A' && c <= 'Z'); }