Homework #1

Coding and comprehension


1. [10] Identify at least one of each of the following in the below code:
   • reserved keywords
   • preprocessing directives
   • variable definitions
   • variable declarations
   • variable initialization
   • user input
   • output
   • function

   #include 
   int main()
   {
       std::cout << "Enter two numbers:" << std::endl;
       int v1, v2;
       std::cin >> v1 >> v2;
       std::cout << "The sum of " << v1 << " and " << v2
                 << " is " << v1 + v2 << std::endl;
       return 0;
   }
   

2. [5] What is the output of the above code after each of these inputs?

   - 4 7
   - 17 23
   - 5.6 3.2
   



3. [10] Write a program to print "Hello, World" on the standard output.


4. [9] Indicate which, if any, of the following output statements, are legal.

   std::cout << "/*";
   std::cout << "*/";
   std::cout << /* "*/" */;
   

   After you've predicted what will happen, test your answer by compiling a program with these three statements. Indicate the differences between your predicted output and what you learn from the compiler in your answer.

Data types and variables


5. [2] What is the difference between an int, a long, and a short value?
6. [2] What is the difference between an unsigned and a signed type?
7. [2] If a short on a given machine has 16 bits then what is the largest number that can be assigned to a short? To an unsigned short?
8. [2] What value is assigned if we assign 100,000 to a 16-bit unsigned short? What value is assigned if we assign 100,000 to a plain 16-bit short?
9. [8] Using escape sequences, write a program to print 2M followed by a newline. Modify the program to print 2, then a tab, then an M, followed by a newline.
10. [6] Distinguish between an lvalue and an rvalue; show examples of each.
11. [4] What, if any, are the differences between the following definitions:

    int month = 9, day = 7;
    
    int month = 09, day = 07;
    

12. [5] What is the difference between the following two statements?

    int i = 10, r = i;
    
    int i = 10, &r = i;