CPSC 120 Pre-Lab Assignment: Lab #2

  1. What is the difference between a variable and a constant?



  2. Write Java code to do each of the following:
    1. Set up storage for (that is, declare) an integer variable count without giving it an initial value.


    2. Set up storage for an integer variable count and give it an initial value of 0.


    3. Set count to 5, assuming that it has already been declared as an integer variable.


    4. Set count to one more than its current value, assuming that it has already been declared as an integer variable and currently has a value.


  3. The following program reads three integers and prints the average. Fill in the blanks so that it will work correctly.
    // **********************************************
    // FILE: Average.java
    // Purpose: Read three integers from the user and print their average
    // **********************************************
    import cs1.Keyboard;
    public class Average
    {
      public static void main(String[] args)
      {
        int val1, val2, val3;
        double average;
    
        // get three values from user
        System.out.println("Please enter three integers and " +
                           "I will compute their average");
    
        ____________________________________
    
        ____________________________________
    
        ____________________________________
    
        //compute the average
    
        ____________________________________
    
        //print the average
    
        ____________________________________
      }
    }
    

  4. Given the declarations below, find the result of each expression.
    int a = 3, b = 10, c = 7;
    double w = 12.9, y = 3.2;
    
    1. a + b * c

    2. a - b - c

    3. a / b

    4. b / a

    5. a - b / c

    6. w / y

    7. y / w

    8. a + w / b

    9. a % b / y

    10. b % a

    11. w % y