Some Practice Problems for the C++ Exam and Solutions for the Problems

14 a.  The output will be  "less than 10". 

b.  The output will be  "greater than 15". 

c.  The output will be  "less than 10". 

d.  There is no value for  n  that will cause the output to be  "not interesting".  That part of the 

code can never be executed! 

 

 

15.  Using  do...while... in this situation makes the code a little simpler. 

 

   int n; 

 

   do 

   { 

      cout << "Enter a non-negative integer: "; 

      cin  >> n; 

 

      if (n < 0) 

         cout << "The integer you entered is negative." << endl; 

   } 

   while (n < 0); 

  

 

16 a.  The output of the code fragment as it is written will be 

 

n is not zero. 

The square of n is 0. 

 

 

The  reason  for  this  is  that  the  "if"  part  assigns  the  value    0    to    n  ,  and  the  value  returned  by  that 

assignment  statement  is    0  ,  so  this  is  treated  as  "false",  which  causes  the  alternative  statement  to  be 

executed.  But even though the program prints  "n is not zero.", in fact,  n  does have the value 

zero after the conditional statement is finished.