Submitted by Anonymous (not verified) on Sun, 03/10/2013 - 00:12

Question and Answer

    Q Why do you need to use arrays?

    A In many cases, you need to declare a set of variables that are of the same data type. Instead of declaring each variable separately, you can declare all variables collectively in the format of an array. Each variable, as an element of the array, can be accessed either through the array element reference or through a pointer that references the array.

    Q What is the minimum index in an array?

    A In C, the minimum index of a one-dimensional array is 0, which marks the first element of the array. For instance, given an integer array,

    int array_int[8];

    the first element of the array is array_int[0].

    Likewise, for a multidimensional array, the minimum index of each dimension starts at 0.

    Q How do you reference an array by using a pointer?

    A You can use a pointer to reference an array by assigning the start address of an array to the pointer. For example, given a pointer variable ptr_ch and a character array array_ch, you can use one of the following statements to reference the array by the pointer:

    ptr_ch = array_ch;

    ptr_ch = &array_ch[0];

    Q What can the null character do?

    A The null character (\0) in C can be used to mark the end of a string. For instance, the printf() function puts the next character on the screen when the null character is encountered. Also, the null character always returns FALSE in a logical test.

 

 

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