Program 1)

import java.util.*;
class ComputeElectricityBill
{
        public static void main(String args[])
        {  
   long units;
 
   Scanner sc=new Scanner(System.in);
 
   System.out.println("enter number of units");
  
           units=sc.nextLong();
 
        double billpay=0;
 
           if(units<100)
billpay=units*1.20;
 
         else if(units<300)
billpay=100*1.20+(units-100)*2;
 
    else if(units>300)
billpay=100*1.20+200 *2+(units-300)*3;

              System.out.println("Bill to pay : " + billpay);

Program 2)

import java.util.Scanner;

class RailwayTicket {
String name;
String coach;
long mobno;
int amt;
int totalamt;

void accept() {
Scanner scanner = new Scanner(System.in);
System.out.print("Enter name: ");
name = scanner.nextLine();
System.out.print("Enter coach:(Type 1A for first class, 2A for second class, 3A for third class &
SL for Sleeper class) ");
coach = scanner.nextLine();
System.out.print("Enter mobno: ");
mobno = scanner.nextLong();
System.out.print("Enter amt: ");
amt = scanner.nextInt();
}

void update() {
if (coach.equals("1A")) {
totalamt = amt + 700;
} else if (coach.equals("2A")) {
totalamt = amt + 500;
} else if (coach.equals("3A")) {
totalamt = amt + 250;
} else if (coach.equals("SL")) {
totalamt = amt;
}
}

void display() {
System.out.println("Name: " + name);
System.out.println("Coach: " + coach);
System.out.println("Mobile Number: " + mobno);
System.out.println("Amount: " + amt);
System.out.println("Total Amount: " + totalamt);
}
}
class Driver{
public static void main(String args[]) {
RailwayTicket rt = new RailwayTicket();
rt.accept();
rt.update();
rt.display();
}

Program 3a)

import java.util.Scanner;

public class Example11 {

Scanner sc = new Scanner(System.in);

System.out.print("Input a number : ");

int num = sc.nextInt();

int copy = num, d = 0, sum = 0;

String s = Integer.toString(num);

int len = s.length();

while(copy>0)

d = copy % 10;

sum = sum + (int)Math.pow(d,len);

len--;

copy = copy / 10;

if(sum == num)

System.out.println("Disarium Number.");

else

System.out.println("Not a Disarium Number.");

Program 3b)

import java.util.HashSet;
import java.util.Scanner;

import java.util.Set;

public class Example10 {

public static boolean isHappy_number(int num)

Set<Integer> unique_num = new HashSet<Integer>();

while (unique_num.add(num))

int value = 0;

while (num > 0)

value += Math.pow(num % 10, 2);

num /= 10;

num = value;

return num == 1;

public static void main(String[] args)

{
 System.out.print("Input a number: ");

int num = new Scanner(System.in).nextInt();

System.out.println(isHappy_number(num) ? "Its a Happy Number" : "Its an Unhappy Number");

Program 4)

import java.util.Scanner;

public class ISBN {

    public static void main(String[] args) {

        Scanner scanner = new Scanner(System.in);

        System.out.print("Enter ISBN code: ");

        long isbnInteger = scanner.nextLong();

        String isbn = isbnInteger + "";

        if (isbn.length() != 10) {

            System.out.println("Ilegal ISBN");

        } else {
             int sum = 0;

            for (int i = 0; i < 10; i++) {

                int digit = Integer.parseInt(isbn.charAt(i) + "");

                sum = sum + (digit * (i + 1));

            }

            if (sum % 11 == 0) {

                System.out.println("Legal ISBN");

            } else {

                System.out.println("Illegal ISBN");

            }

        }

    }

Program 5 )

Pattern 1)

public class MainClass

{
public static void main(String[] args)

int rows = 9;

//Printing upper half of the pattern

for (int i = 1; i <= rows; i++)

//Printing i to rows value at the end of each row

for (int j = i; j <= rows; j++)

System.out.print(j);

//Printing i spaces at the beginning of each row

for (int j = 9; j > i; j--)

System.out.print(" ");

System.out.println();

//Printing lower half of the pattern

//Printing i to rows value at the end of each row

for (int j = i; j <= rows; j++)

System.out.print(j);

//Printing i spaces at the beginning of each row

for (int j = 9; j > i; j--)

System.out.print(" ");

System.out.println();

Pattern 2)

class Pat_1_121_12321

{
public static void main(String args[])

int n = 4;

int m = n;

for(int i = 1; i <= m; i++)

for(int j = 1; j <=i; j++)

System.out.print(j);

for(int k = i - 1; k >=1; k--)

System.out.print(k);

System.out.println();

m = n - 1;

for(int i = m; i >=1; i--)

for(int j = 1; j <= i; j++)

System.out.print(j);

for(int k = i - 1; k >= 1; k--)

System.out.print(k);

System.out.println();

}
}

Pattern 3)

public class AlphabeatTriangle4

public static void main(String[] args)

for(int i = 5; i >= 1; i--) //for 4 loops

{for(int j = 1; j <= 5-i; j++)

System.out.print(" "); //for spaces

for(int j = 1; j <= 2*i-1; j++)

if(j <= i)

System.out.print((char)(char)(j+64)+" "); //for printing values

else

System.out.print((char)(char)(2*i-j+64)+" "); //for printing values

System.out.println(); //for line break

Program 6)

public class methodoverload{

int sum(int a,int b){

int tsum=0;

for(int i=a;i<=b;i++){

if(i%2==0)

tsum=tsum+i;
else

tsum=tsum;

return tsum;

double sum(double n){

double pro=1.0;

for(double i=1.0;i<=n;i+=0.2){

pro=pro*i;

return pro;

int sum(int n){

int s=0;

int d;

while(n>0)

d=n%10;

s=s+d;

n=n/10;

return s;

public static void main(String args[]){

methodoverload m=new methodoverload();

System.out.println(m.sum(123));

System.out.println(m.sum(1345518264));

Program 7i)

import java.util.Scanner;

public class series {

public static void main(String[] args) {

Scanner sc = new Scanner (System.in);

int val=0,val1=1,sum=1;

System.out.println ("Enter Value For n:");

int n= sc.nextInt();

for(int i=0;i<n-1;i++)

int k=val+val1;

sum+=k;

val=val1;

val1=k;
}

System.out.println(sum);

}}

Program 7ii)

import java.util.Scanner;

public class SumOfSeries

public static void main(String args[])

Scanner sc = new Scanner (System.in);

int sum =0;

System.out.println("Enter value for n :");

int n= sc.nextInt();

for(int i=2;i<=n;i=i+2)

if(i%4==0){ sum=sum-i;}

else{ sum=sum+i;}

System.out.println(sum);

}
}

Program 7iii)

import java.util.Scanner;//Importing Scanner

public class SeriesSum //Creating Class

public static void main(String[] args) //The main function

Scanner sc = new Scanner(System.in); //Creating Scanner Object

//Take User Input for 'a'

System.out.print("Enter the value of 'a': ");

double a = sc.nextDouble();

//Take User Input for number of terms (n)

System.out.print("Enter the number of terms: ");

int n = sc.nextInt();

double Sum = 0; //Initialise Sum to 0

for(int i=0;i<n;i++) //Run a loop n times

//Add Terms to Sum

Sum += Math.pow(-1,i) * Math.pow(a,(2*i+1));

//Print Final Series Sum

System.out.println(Sum);

}
}

Program 8)

public class Overloading {

public void num_calc(int num, char ch) {

if (ch == 's') {

double square = Math.pow(num, 2);

System.out.println("Square is " + square);

} else {

double cube = Math.pow(num, 3);

System.out.println("Cube is " + cube);

}
public void num_calc(int a, int b, char ch) {

if (ch == 'p') {

int product = a * b;

System.out.println("Product is " + product);

} else {

int sum = a + b;

System.out.println("Sum is " + sum);

public void num_calc(String s1, String s2) {

if (s1.equals(s2)) {
 System.out.println("Strings are same");

} else {

System.out.println("Strings are different");

Program 9)

import java.util.Scanner;

public class StringOperations {

    public static void main(String[] args) {

        Scanner scanner = new Scanner(System.in);

        System.out.print("Enter a String: ");

        input = input.toUpperCase();

        int count = 0;

        for (int i = 1; i < input.length(); i++) {

            if (input.charAt(i) == input.charAt(i - 1)) {

                count++;

            }

        }

        System.out.println(count);

    }

Program 10)

import java.util.*;
public class PiglatinWord
{
    public static void main(String args[])
  {
        Scanner ob=new Scanner(System.in);
        System.out.println("Enter the word to be converted.");
        String word=ob.next();
        word=word.toUpperCase();
        String piglatin="";
        int flag=0;
        for(int i=0;i<word.length();i++)
    {
            char x=word.charAt(i);
            if(x=='A' || x=='E' || x=='I' || x=='O' ||x=='U')
      {
                piglatin=word.substring(i)+word.substring(0,i)+"AY";
                flag=1;
                break;
      }
    }
        if(flag==0)
    {
            piglatin=word+"AY";
    }

        System.out.println(word+" in Piglatin format is "+piglatin);

Program 12)

import java.util.Scanner;

public class Frequency {

public static void main(String[] args) {

Scanner scanner = new Scanner(System.in);

String input = scanner.next();

int[] frequency = new int[65];

for (int i = 0; i < input.length(); i++) {

char ch = input.charAt(i);

int index = ch - 65;

frequency[index]++;

System.out.println("Character - Frequency");

for (int i = 0; i < 26; i++) {

System.out.println((char) (i + 65) + " " + frequency[i]);

Program 13)

import java.util.Scanner;

class SearchMenu

public static void main( )

int counter, num = 10, item, array[],choice;

//Creating array to store the all the numbers

array = new int[num];

Scanner sc = new Scanner (System.in);

System.out.println("Enter 10 integers");
//Loop to store each numbers in array

for (counter = 0; counter < num; counter++)

array[counter] = sc.nextInt();

System.out.println("Enter type of search: 1. Linear/ 2. Binary");

choice = sc.nextInt();

switch (choice)

case 1: System.out.println("Enter the search value:");

item = sc.nextInt();

for (counter = 0; counter < num; counter++)

if (array[counter] == item)

System.out.println(item+" is present at location "+(counter+1));

/*Item is found so to stop the search and to come out of the

* loop use break statement.*/

break;

if (counter == num)

System.out.println(item + " doesn't exist in array.");

case 2:System.out.println("Enter the search value:");

int first = 0;

int last = num - 1;

int middle = (first + last)/2;

while( first <= last )

if ( array[middle] < item )

first = middle + 1;

else if ( array[middle] == item )

System.out.println(item + " found at location " + (middle + 1) + ".");

break;

else

last = middle - 1;

middle = (first + last)/2;

if ( first > last )

System.out.println(item + " is not found.\n");

}
 Default : System.out.println ("Invalid option");

Program 14)

import java.util.Scanner;

public class Alphabetical_Order

public static void main( )

int n = 50;

String temp;

String names[] = new String[n];

Scanner s1 = new Scanner(System.in);

System.out.println("Enter all the names and weights:");

for(int i = 0; i < n; i++)

names[i] = s1.nextLine();

for (int i = 0; i < n; i++)

for (int j = i + 1; j < n; j++)

if (names[i].compareTo(names[j])>0)

{
 temp = names[i];

names[i] = names[j];

names[j] = temp;

System.out.print("Names in Sorted Order:");

for (int i = 0; i < n - 1; i++)

System.out.print(names[i] + ",");

System.out.print(names[n - 1]);

Program 15)

import java.util.Scanner;

public class UpperTriangular

public static void main(String[] args) {

Scanner sc = new Scanner (System.in);

int M [ ] [ ], rows, cols ;

System.out.println ("enter the matrix size :");

int n= sc.nextInt ();

//Initialize matrix n

M= new int [n] [n];

for (int i=0; i<n; i++)

for (int j=0; j<n; j++)

M[ i ] [ j ]= sc.nextInt ();

//Calculates number of rows and columns present in given matrix

rows = M.length;

cols = M[0].length;

if(rows != cols){

System.out.println("Matrix should be a square matrix");

else {

//Performs required operation to convert given matrix into upper triangular matrix

System.out.println("Upper triangular matrix: ");

for(int i = 0; i < rows; i++){

for(int j = 0; j < cols; j++){

if(i > j)

System.out.print(" ");

else

System.out.print(M[i][j] + " ");

System.out.println();