isspace : char functions « Data Types « C++ Tutorial

1. C++ Tutorial
2. Data Types
3. char functions

#include <iostream>
using std::cout;
using std::endl;

#include <cctype>
using std::iscntrl;
using std::isgraph;
using std::isprint;
using std::ispunct;
using std::isspace;

int main()
{
   cout << "According to isspace:\nNewline " 
      << ( isspace( '\n' ) ? "is a" : "is not a" )
      << " whitespace character\nHorizontal tab " 
      << ( isspace( '\t' ) ? "is a" : "is not a" )
      << " whitespace character\n"
      << ( isspace( ' is a" : " is not a" )
      << " whitespace character\n";
   return 0;
}

According to isspace:
Newline is a whitespace character
Horizontal tab is a whitespace character
% is not a whitespace character