Home Segments Index Top Previous Next 
289: Sidetrip 

You can, if you wish, use conditional-operator expressions in place 
of if statements, as in the following example, in which 
one of the two output expressions is evaluated: 

#include  
main ( ) { 
  int change; 
  cin >> change; 
  change == 1 ? cout << "The temperature has changed by " 
                     << change << " degree." << endl 
              : cout << "The temperature has changed by " 
                     << change << " degrees." << endl; 
} 
--- Data ---
1 
--- Result --- 
The temperature has changed by 1 degree. 

 
This program not only reintroduces needless duplication, but also 
introduces a conditional-operator expression that is not inside any other 
expression that can make use of the value produced.  Instead, the 
conditional-operator expression forms a complete statement.  Such use of 
the conditional operator is considered poor programming practice, and your 
C++ compiler should issue a warning.