int isalnum(int c) {
return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9');
}
int isalpha(int c) {
return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z');
}
int isblank(int c) {
return c == ' ' || c == '\t';
}
int iscntrl(int c) {
return (c >= 0 && c <= 31) || c == 127;
}
int isdigit(int c) {
return c >= '0' && c <= '9';
}
int isgraph(int c) {
return c > 32 && c < 127;
}
int islower(int c) {
return c >= 'a' && c <= 'z';
}
int isprint(int c) {
return c >= 32 && c < 127;
}
int ispunct(int c) {
return isgraph(c) && !isalnum(c);
}
int isspace(int c) {
return c == ' ' || c == '\t' || c == '\n' || c == '\r' || c == '\f' || c == '\v';
}
int isupper(int c) {
return c >= 'A' && c <= 'Z';
}
int isxdigit(int c) {
return isdigit(c) || (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F');
}
int tolower(int c) {
if (c >= 'A' && c <= 'Z') {
return c + ('a' - 'A');
}
return c;
}
int toupper(int c) {
if (c >= 'a' && c <= 'z') {
return c - ('a' - 'A');
}
return c;
}