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An alternative to the ! operator.

#define not !  

The macro yields the operator !.

// iso646_not.cpp  
// compile with: /EHsc  
#include <iostream>  
#include <iso646.h>  
int main( )  
   using namespace std;  
   int a = 0;  
   if (!a)  
      cout << "a is zero" << endl;  
   if (not(a))  
      cout << "a is zero" << endl;  

a is zero  
a is zero  

Header: <iso646.h>