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St40_Name = "Aadarsh";
                 It easy to follow this process if the number of pens is less. What happened when the number of students is 1000 or
                 more? In that case, it is very time consuming and time taking process to maintain 1000 variables or more. But with the
                 help of arrays, it is very easy task to do so.

                 15.1.1 Array as a Composite Type
                 Composite types are those which contains a number of same or different types of data using a single declaration. As an
                 array is a collection of same type of data, so it can be referred as a composite date type or a non-primitive data type.


                     15.2 TYPES OF ARRAYS
                 In Java, there are two types of arrays:
                 •  Single Dimensional Array
                 •  Multi-Dimensional Array
                 Let us study about them in detail.


                 15.2.1 Single Dimensional Array
                 A single dimensional  array is  a type  of array with  single  subscript. It contains  the values either row-wise or
                 column-wise.

                 Declaring a Single Dimensional Array
                 We  can declare  a single dimensional  array  with the  help  of primitive  data types. The syntax to declare  a single
                 dimensional array is:
                   <data type> <array name>[] = new <data type>[size of array];
                 You can also use the first square brackets before the <array name> like:
                   <data type>[] <array name>  = new <data type>[size of array];
                 Whare, <data type> is valid primitive data type like int, float, double, etc. <array name> is the valid Java identifier, [ ]
                 represents array declaration, new is the operator to initialize an array and [size of array] signifies the size of an array.
                 Size of an array is always be an integer number like 2, 4, 7, 12 20, etc. It represents the number of items can be stored
                 in an array. An item in an array is called an element. Each element of the array associate with an index started from 0.
                 Index is also known as subscript.

                 Let us create an array to store the names and roll numbers of 40 students in the following manner:
                   String names[] = new String[40];    //To store the names of students
                   int roll_no[] = new int[40];       //To store the roll numbers of the students
                 Java also allows you declare and initialize an array separately in the following manner:

                   String names[];            //Declaring an array
                   names = new names[40];    //Initializing an array
                 An array stores the values in contiguous memory locations. The memory representation of an array elements is shown
                 below:

                 Array Index         names[0] names[1] names[2] names[3]         …       …       …       …    names[39]
                 Values              Amit      Ajay       Harry     Raj          …       …       …       …    Ramit
                 Memory Address      58421     58422      58423     58424        …       …       …       …    58460

                 Array Index         roll_no[0]  roll_no[1]  roll_no[2]  roll_no[3]   …        …       …     roll_no[39]
                 Values              1          2           3           4             …        …       …     40
                 Memory Address      69406      69407       69408       69409         …        …       …     69445




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