Computer Science I
CISC-1600-E01 Final Examination
Thursday, December 19, 2024
jsr1 John S. Rodriguez

1. Suppose you had to write a C++ program that outputs 10 consecutive ints. Why would it be more natural and useful in this language to output the ints from 0 to 9 inclusive, rather than the ints from 1 to 10 inclusive?
2. Assume you already have a variable named n, of type int, containing some value. Do not create this variable: assume it already exists. Write C++ code that will output the first message (and only the first message) that is applicable in the following list.
   1. “very big” if n is greater than 1,000,000
   2. “pretty big” if n is greater than 100,000
   3. “fairly big” if n is greater than 10,000
   4. “big” if n is greater than 1,000
   5. “small” if n is less than or equal to 1,000
   After the message, output one newline character.
3. [Multiple choice.] In what order do the three variables in the following C++ code die?

   void f();
   
   int main()
   {
   	f();
   	int k {20};
   	return EXIT_SUCCESS;
   }
   
   void f()
   {
   	int j {10};
   
   	for (int i {0}; i < 10; ++i) {
   		cout << j << "\n";
   	}
   }
   

   1. i, j, k
   2. i, k, j
   3. j, i, k
   4. j, k, i
   5. k, i, j
   6. k, j, i
4. Horseshoes are sold in packs of four, because a horse has four feet. Assume you already have a variable named nshoes, of data type int, containing the number of horseshoes you have. Do not create this variable: assume it already exists. Now create a variable named npacks, of type int, whose value is the number of complete packs you can make out of nshoes horseshoes. And create another variable named nleftovers, of type int, whose value is the number of loose horseshoes left over after you make all the possible packs out of nshoes horseshoes. (The value of nleftovers will be an int in the range 0 to 3 inclusive.)
5. Write the definition of a recursive C++ function named asterisks, whose formal argument is an int named n. The function will output (to cout) a row of n asterisks. The function will use recursion instead of a loop, and will do the following things:
   1. Check for error. If the formal argument n is negative, the function asterisks will output (to cerr) an error message and terminate the program by passing the argument EXIT_FAILURE to the C++ function exit.
   2. If the formal argument n is positive, the function asterisks will output (to cout) one asterisk, and will then call itself to output the remaining n-1 asterisks.
   3. If the formal argument n is zero, the function asterisks will do nothing, because no work remains to be done.
6. Create a C++ variable named d, of data type double, born holding the value 3.14159. Then output (to cout) the value of this variable, followed by one newline character.
7. [Multiple choice.] In the following C++ statement, in what order are the operators executed?

   	i = 20 * j + k;
   

   1. =, *, +
   2. =, +, *
   3. *, =, +
   4. *, +, =
   5. +, =, *
   6. +, *, =
8. Write the definition of a C++ function named mpg, that returns a value of type double telling you how many miles per gallon of gas you’re getting. The two formal arguments of this function should be doubles named miles and gallons.
   1. If the value of the formal argument gallons is less than or equal to 0, the function should output (to cerr) an error message saying that the number of gallons must be positive, and should terminate the program by passing the argument EXIT_FAILURE to the C++ function exit.
   2. If the value of the formal argument gallons is positive, the function mpg should return the number of miles per gallon that you’re getting.
9. What is output by the following C++ code?

   	int i {10};
   	int j {i};
   	int k {20};
   	int& r {k};
   
   	++j;
   	++r;
   
   	cout << i << "\n";
   	cout << k << "\n";
   

10. Assume you already have an array of ints named a. Do not create this array: assume it already exists. Write C++ code that will output (to cout) the smallest value in the array. But if the array contains no values (i.e., if the array is of length zero), your code should output (to cerr) a message saying that there is no smallest value in the array.
11. Assume you already have two arrays of ints, named source and dest, of equal length. Do not create these arrays: assume they already exist. Write C++ code that will copy all the values from the source array into the dest array.
12. Definitions.
    1. What is a computer?
    2. What is a program?
13. Write a C++ loop that produces the following output:

    0
    8
    16
    24
    32
    40
    48
    56
    64
    72
    

    Extra credit. Right justify the column of numbers, because that’s the way human beings like to see it. Is there any file you would need to #include in order to right justify?

     0
     8
    16
    24
    32
    40
    48
    56
    64
    72
    

14. Create a new C++ data type named person. A variable of this new data type will contain three values inside of it:
    1. A string named lastName, giving the last name of the person.
    2. A string named firstName, giving the first name of the person.
    3. An int named age, giving the age in years of the person.
    Then create one variable named founder, of data type person, born holding the three values "Ignatius", "Loyola", and 64. Then write code that gets the three values from founder and outputs them (to cout) on three separate lines.
15. [Array of structures.] Create an array named a, containing 5 of the persons of the previous problem. You can make up any values for the three fields in each person. Then write C++ code that will output (to cout) the first and last names of the person with the highest age in the array. If two or more persons have the highest age, output the first and last names of the first person in the array that has that age.

    If the array contains no persons (i.e., if the array is of length zero), your code should output (to cerr) a message saying that there is no highest age in the array. This will not happen, since your array contains 5 persons. But put it in anyway, just in case someone else tampers with the array.

16. Write the definition of a C++ function named clamp whose formal argument, named n, is of data type “reference to int”. If the value of the argument is less than 0, the function will change the value of the argument to 0. If the value of the argument is greater than 100, the function will change the value of this argument to 100.
17. Find a more straightforward way of producing the same output as the following C++ code.

    	if (hour >= 12) {
    		if (hour < 12 + 6) {
    			cout << "Good afternoon.\n";
    		} else if (hour < 12 + 9) {
    			cout << "Good evening.\n";
    		} else {
    			cout << "Good night.\n";
    		}
    	} else {
    		cout << "Good morning.\n";
    	}
    

18. Write a complete C++ program that outputs (to cout) the following three lines

    New York
    New Jersey
    Connecticut
    

    and then produces the value EXIT_SUCCESS as its exit status.
19. Assume you already have an array of doubles named a. Do not create this array: assume it already exists. Write C++ code that will output (to cout) the average of all the positive values in the array. If the array contains no positive values, your code should output (to cerr) a message saying there are no positive values in the array.
20. What does the following C++ code output?

    	int i {5};
    	int j {2};
    	cout << i/j << "\n"; 
    
    	double d {5.0};
    	double e {2.0};
    	cout << d/e << "\n";