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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."


    Given a char pointer, ptr_ch, an int pointer, ptr_int, and a float pointer, ptr_flt, how many bytes will be added, respectively, in the following expressions on your machine?
        ptr_ch + 4
        ptr_int + 2
        ptr_flt + 1
        ptr_ch + 12
        ptr_int + 6
        ptr_flt + 3

    If the address held by an int pointer, ptr1, is 0x100A, and the address held by another int pointer, ptr2, is 0x1006, what will you get from the subtraction of ptr1-ptr2?
    Given that the size of the double data type is 8 bytes long, and the current address held by a double pointer variable, ptr_db, is 0x0238, what are the addresses held, respectively, by ptr_db-1 and ptr_db+5?
    Given the following declarations and assignments:

    char ch[] = {`a', `b', `c', `d', `A', `B', `C', `D'};
    char *ptr;
    ptr = &ch[1];

        what do these expressions do separately?

        *(ptr + 3)
        ptr - ch
        *(ptr - 1)
        *ptr = `F'
 

    Given a character string, I like C!, write a program to pass the string to a function that displays the string on the screen.
    Rewrite the program of exercise 1. This time, change the string of I like C! to I love C! by moving a pointer that is initialized with the start address of the string and updating the string with new characters. Then, pass the updated string to the function to display the content of the string on the screen.
    Given a two-dimensional character array, str, that is initialized as

    char str[2][15] = { "You know what,", "C is powerful." };

    write a program to pass the start address of str to a function that prints out the content of the character array.

    Rewrite the program in Listing 16.7. This time, the array of pointers is initialized with the following strings:

    "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", and "Saturday".

 

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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?