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darKLoin
darKLoin

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day-03

#java #beginners

DAY-03
Index
01.Break Lable
02.Continue Lable
03.Array
04.2D-Array
05.Class/Object
06.Extra problem
06.1: Write a JAVA program to find simple interest.
06.2: Definging a class called Student.Observe the members of the class i.e. the data and function.
06.3: Write the JAVA program that prompts the user for an integer and then prints out all prime numbers up to that integer.
06.4: Write a JAVA program that checks whether a given string is palindrome or not?
06.5: Write a JAVA program to fine the biggest & smallest number from the given array of 10 integers.
06.6: Write a JAVA program to sort given of 10 integers in ascending & descending order.
06.7: Write a JAVA program to delete an element from an array of 10 elements.
06.8: Write a JAVA program that prints transpose of given matrix.

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----------------------------------01------------------------------

  1. Lable Break ~Lable Break: lable break means, coming out of a labled block of code OR braking the mentioned loop or block of code. it also work as a go to statement lable: is a identifire which identifies the some block of code. Systax: } { ...//statement }break lable; example: 01.1:write a simple program to show the use and working of'break lable;' 
class lable { public static void main(String args[]) { boolean hell = true; first: { second: { third: { System.out.println("in third block of code"); if(hell) break second; System.out.println("after bresk second,, in third block of code."); } System.out.println("in second block of code."); } System.out.println("in first block of code."); } } }
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example: 01.2: write a loop program to show the use of break lable.
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class lablebreak { public static void main(String args[]) { first: for(int i = 0; i<100;i++) { second: for(int j =10 ; j<100 ; i++ ) { third: for(int k =0 ; k <5; k++) { ............................................................................ } } } } }
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~if lable break is not there in the block or the loop then it will give the error.
like

class errcheck { public static void main(String args[]) { fail: for(int i = 5 ; i<50 ;i++) System.out.println("hello this will excute with out loop."); second: for(int j =21; j<30; j++) { if(j==25) break fail; System.out.println("after breaking fail."); } } }
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~ error will look like this

Main.java:11: error: undefined label: fail break fail; ^ 1 error exit status 1
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--------------------------------02--------------------------------

  1. Lable continue
    ~ Lable Continue is work to skip some further steps of the loop or block of code in labled block.

    example: 02.1: write a program to show the use of continue lable.

class contlable { public static void main(String args[]) { int i,j; first: for( i = 0 ; i<10 ; i++) { second: for( j = 0 ; j<10 ; j++) { if(j>i) { System.out.println(" "); continue first; } System.out.print(" "+i*j); } } System.out.println(""); } }
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  1. Array
    ~Array: it stores the data of same data type with consecutive order of memory.
    ~decleration:
    DataType ArrayName[] = new dataType[Size];
    int arr[] = new int[50];
    int arr[] = {1,2,4,5,6,8,4,7,4};

    example: 03.1: write a program to get the average double element of an array.

class arro { public static void main(String args[]) { double arr[] = {1.1,1.2,1.3,2.1,2.2,2.3,2.4}; double result = 0, avg =0 ; for(int i = 0 ; i<arr.length; i++) { result = result+arr[i]; } avg = result / arr.length; System.out.println("the average of given array is: "+avg); } }
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example: 03.2: write a program to get the average of an array.(size and element are input from user)
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import java.util.Scanner; class arr { public static void main(String args[]) { Scanner sc = new Scanner(System.in); int result =0; double avg = 0; System.out.println("Enter the size of array"); int n = sc.nextInt(); int arr[] = new int[n]; System.out.println("Enter the element for the array"); for(int i= 0 ; i<n; i++) { arr[i] = sc.nextInt(); result = result + arr[i]; } avg = result/arr.length; System.out.println("The average of array is: "+avg); } }
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04.2D-Array
~2D-Array: 2D-array are the same as the array but it stores the another dimension of the array
as shown in example:
example: 04.1: write a program to show the two dimensional array by taking input.

class 2darr { public static void main(String args[]) { int i,j,k=0; int arr[][] = new int[4][4]; for(i = 0 ; i< 3 ; i++) { for(j =0 ; j<3 ; j++) { arr[i][j] = k ; k++; } } for(i =0 ; i<3 ; i++) { for(j =0 ; j <3 ; j++) { System.out.print(" "+arr[3][3]); } System.out.println(""); } } }
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~we can decleare a 2-D in different ways
by taking input from user
by decleareing the different variable for different or outer position as declerared
int two[][] = new int[3][];
two[1] =new int[1];
two[2] = new int[2];
two[3] = new int[3];

by declearing the inner variable with respect of outer variable int two[3][4] = new int[3][]; two[0] =new int[4]; two[2] =new int[4]; two[3] =new int[4];
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05.Class/Object
~there are two types of objects normally
1. tangible objects:- pen, desktop , bike, bottel.
2. intangible objects:- account , fee , air , marks.

~every objects have different states adn behaviours like
dog: states(name, color, bread,appetite) behaviour(bark,run,fetching)

class: it is the set of property behaviour which all entites in objects list.
include the all property(states, behaviour) in them for the similar objects.
it is also known as blueprint-n objects.

 the different propety(states,behaviour) is also known as instance variable(states) and instance function(behaviour) class is a logical entity and objects is physical entity for example class laptop { float weight; int processer; float model; float color; float rate; //above all are the class member/instance variable/variable member void broucher() { float all = model+color+rate+weight; System.out.printnl(" "+all); } //this is the class behacviour/instance function it uses the states of class } objects are created dynamicaly like lapotopIdentifire Creation of a class is a creation of a datatype and object creatation is creation of variable to use class datatype create a object as laptop dell = new laptop(); laptop hp = new laptop(); laptop intel = new laptop(); here 'laptop();' is work as a constructor object is also known as instance of a class example: create a class and object
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class laptop
{
float weight;
float model;
float color;
float rate;
void broucher()
{
float all = model+color+rate+weight;
System.out.printnl(" "+all);
}
}

class laptopIdentifier { public static void main(String args[]) { laptop obj1 = new laptop(); obj1.weight = 230.44f; obj1.model = 239944X; obj1.color = #112233; obj1.rate = 66000.0; obj1.broucher(); laptop obj2 = new laptop(); obj2.weight = 465.44f; obj2.model = 654167Y; obj2.color = #458932; obj2.rate = 85200.0f; obj2.broucher(); laptop obj3 = new laptop(); obj3.weight = 850.00f; obj3.model = 5448131A; obj3.color = #789522; obj3.rate = 239000.0; obj3.broucher(); } } ``` ---------------------------------END------------------------------ ---------------------------------06------------------------------- 06.Extra problem ~problem 06.1: Write a JAVA program to find simple interest. ~problem 06.2: Definging a class called Student.Observe the members of the class i.e. the data and function. ~problem 06.3: Write the JAVA program that prompts the user for an integer and then prints out all prime numbers up to that integer. ~problem 06.4: Write a JAVA program that checks whether a given string is palindrome or not? ~problem 06.5: Write a JAVA program to fine the biggest & smallest number from the given array of 10 integers. ~problem 06.6: Write a JAVA program to sort given of 10 integers in ascending & descending order. ~problem 06.7: Write a JAVA program to delete an element from an array of 10 elements. ~problem 06.8: Write a JAVA program that prints transpose of given matrix.
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