Submitted by tushar pramanick on Fri, 03/08/2013 - 00:25

To help solidify your understanding of this hour's lesson, you are encouraged to answer the quiz questions and finish the exercises provided in the Workshop before you move to the next lesson. The answers and hints to the questions and exercises are given in Appendix E, "Answers to Quiz Questions and Exercises."
Quiz

    Given x = 0, will the arithmetic operations inside the following if statement be performed?

    if (x != 0)
       y = 123 / x + 456;


    Given x = 4, y = 2, and operator = `-', what is the final value of x after the following switch statement is executed?

    switch (operator){
       case `+':  x += y;
       case `-':  x -= y;
       case `*':  x *= y;
       case `/':  x /= y;
       default:   break;
    }


    Similarly to in question 2, using x = 4, y = 2, and operator = `-', what is the final value of x after the following switch statement is executed?

    switch (operator){
       case `+':  x += y; break;
       case `-':  x -= y; break;
       case `*':  x *= y; break;
       case `/':  x /= y; break;
       default:   break;
    }


    What is the value of the integer variable x after the following code is executed?

    x = 1;
    for (i=2; i<10; i++){
       if (i%3 == 0)
          continue;
       x += i;
    }


Exercises

    Rewrite the program in Listing 10.1. This time, use the logical expression i%6 == 0 in the if statement.
    Rewrite the program in Listing 10.1 by using nested if statements.
    Write a program to read characters from the standard I/O. If the characters are A, B, and C, display their numeric values on the screen. (The switch statement is required.)
    Write a program that keeps reading characters from the standard input until the character q is entered.
    Rewrite the program in Listing 10.7. This time, instead of skipping 3 and 5, skip the integer that can be divided evenly by both 2 and 3.

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Exercises : Answer the following Question

To help solidify your understanding of this hour's lesson, you are encouraged to answer the quiz questions and finish the exercises provided in the Workshop before you move to the next lesson.

Question and Answer

    Q Why is random access to a disk file necessary?