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The following code will not compile or run. WHY?

LESSON 8: WRAPPER CLASSES IN JAVA ✅Wrapper classes provide a way to use primitive data types (int, boolean, etc..) as objects. ✳️Sometimes you must use wrapper classes, for example when working with Collection objects, such as ArrayList, where primitive types cannot be used (the list can only store objects): example: ArrayList<Integer> myNumbers = new ArrayList<Integer>(); // Valid Creating Wrapper Objects To create a wrapper object, use the wrapper class instead of the primitive type. To get the value, you can just print the object: Example

public class Main {
  public static void main(String[] args) {
    Integer myInt = 5;
    Double myDouble = 5.99;
    Character myChar = 'A';
    System.out.println(myInt);
    System.out.println(myDouble);
    System.out.println(myChar);
  }
}

//

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LESSON 7: LOOPS AND NESTED LOOPS ✳️Looping in java helps by facilitating the execution of of a set of instructions repeatedly while some condition evaluates to true. 1. While-loops: allows the code to be executed repeatedly based on a given Boolean condition.

   while (boolean condition)
     {
   loop statements...
   }

2. for-loops: unlike while statement, it consumes the initialization, condition, and increment/decrement. for (initialization condition; testing condition; increment/decrement) { statement(s) } 3. do-while: do while loop is similar to while loop with only difference that it checks for condition after executing the statements. do { statements.. } while (condition); sample example for for-loop:

public class Loops
{
    public static void main(String[] args)
    {
        ArrayList<Integer> ar = new ArrayList<>();//we will see about list in the next lessons
        for (int i = 0; i < Integer.MAX_VALUE; i++)
        {
            ar.add(i);
        }
    }

} link to get our Channel» https://t.me/PROGRAMINGLANGUAGES1» group for your comments» https://t.me/learntocodecpp

LESSON 7: LOOPS AND NESTED LOOPS ✳️Looping in java helps by facilitating the execution of of a set of instructions repeatedly while some condition evaluates to true. 1. While-loops: allows the code to be executed repeatedly based on a given Boolean condition.

   while (boolean condition)
     {
   loop statements...
   }

2. for-loops: unlike while statement, it consumes the initialization, condition, and increment/decrement. for (initialization condition; testing condition; increment/decrement) { statement(s) } 3. do-while: do while loop is similar to while loop with only difference that it checks for condition after executing the statements. do { statements.. } while (condition); sample example for for-loop:

public class Loops
{
    public static void main(String[] args)
    {
        ArrayList<Integer> ar = new ArrayList<>();//we will see about list in the next lessons
        for (int i = 0; i < Integer.MAX_VALUE; i++)
        {
            ar.add(i);
        }
    }

} link to get our Channel» https://t.me/PROGRAMINGLANGUAGES1» group for your comments» https://t.me/learntocodecpp

‼️: ignore [a], [b],[c] and [d] it is only to identify the choice

LESSON 6: ARRAY AND 2D ARRAYS ✅An array is a collection of items stored at contiguous memory locations. The idea is to store multiple items of the same type together. ✳️Multidimensional Arrays can be defined in simple words as array of arrays. Data in multidimensional arrays are stored in tabular form (in row major order). *In the array there will be: data_type : type of data to be stored in the array dimension: the dimension of the array is created. like 1D, 2D ... array_name: name of the array finally , the size of the array. #example_of_array:; class CODER { public static void main (String[] args) { // declares an Array of integers. int[] arr; // allocating memory for 5 integers. arr = new int[5]; // initialize the first elements of the array arr[0] = 10; // initialize the second elements of the array arr[1] = 20; //so on... arr[2] = 30; arr[3] = 40; arr[4] = 50; // accessing the elements of the specified array for (int i = 0; i < arr.length; i++) System.out.println("Element at index " + i + " : "+ arr[i]); } } 2D array:- class Learn { public static void main(String[] args) { int[][] arr = new int[10][20]; arr[0][0] = 1; System.out.println("arr[0][0] = " + arr[0][0]); } }