Defined in header <cctype> int isspace( int ch );
Checks if the given character is whitespace character as classified by the currently installed C locale. In the default locale, the whitespace characters are the following:
space (0x20, ' ') form feed (0x0c, '\f') line feed (0x0a, '\n') carriage return (0x0d, '\r') horizontal tab (0x09, '\t') vertical tab (0x0b, '\v')
The behavior is undefined if the value of ch is not representable as unsigned char and is not