SIMPLE JAVA PROGRAMMING

1. Add two numbers in Java.

import java.io.*;
class add
{
public static void main(string args[]) throws IOException
{
int x,y,z;
InputStreamReader is= new InputStreamReader(System.in);
BufferedReader br= new BufferedReader( is );
System.out.println("Enter 1st no");
x=Integer.parseInt(br.readLine());
System.out.println("Enter 2nd no");
y=Integer.parseInt(br.readLine());
z=x+y;
System.out.println("The sum is .. "+z);
}
}

Sample Output :

Enter 1st no
1
Enter 2nd no
1
The sum is .. 2

2. Write a program to accept 3 no and display the largest no.

import java.io.*;
class largest
{
public static void main(string args[]) throws IOException
{
int x,y,z;
InputStreamReader is= new InputStreamReader(System.in);
BufferedReader br= new BufferedReader( is );
System.out.println("Enter 1st no");
x=Integer.parseInt(br.readLine());
System.out.println("Enter 2nd no");
y=Integer.parseInt(br.readLine());
System.out.println("Enter 3rd no");
z=Integer.parseInt(br.readLine());
if((x>y)&&(x>z))
{
System.out.println("Max="+x);
}
else if(y>z)
{
System.out.println("Max="+y);
}
else
{
System.out.println("Max="+z);
}
}
}

Sample Output :
        Enter 1st no
            12
        Enter 2nd no
             11
           Enter 3rd no
              34
              Max=34

3. Write a program to accept a no and display its table.

import java.io.*;

class table

{

public static void main(String args[])Throws IOException

{

int x,n=1;

InputStreamReader is=new InputStreamReader(System.in);

BufferedReader br=new BufferedReader(is);

System.out.println("Enter a no");

x=Integer.parseInt(br.readLine());

while(n<=10)

{

System.out.println(x+"*"+n+"="+x*n);

n++;

}

}

}

Sample Output:

Enter a no  11

11*1=11
11*2=22
11*3=33
11*4=44
11*5=55
11*6=66
11*7=77
11*8=88
11*9=99
11*10=110

4. Write a program to accept a no and calculate its factorial.

import java.io.*;
class factorial
{
public static void main(String args[]) throws IOException
{
int n,c,fact=1;
InputStreamReader is=new InputStreamReader(System.in);
BufferedReader br= new BufferedReader(is);
System.out.println("Enter a no");
n=Integer.parseInt(br.readLine());
if(n<0)
{
System.out.println("Number should be non negetive");
}
else
{
for(c=1;c<=n;c++)
fact=fact*c;
System.out.println("Factorial is .... "+fact);
}
}
}

Sample output :

Enter a no
4
Factorial is .... 24

5. Write a program to accept base and exponent and calculate power for the number.

import java.io.*;
class power
{
public static void main(String args[])throws IOException
{
int x,y,z=1;
InputStreamReader is= new InputStreamReader(System.in);
BufferedReader br=new BufferedReader(is);
System.out.println("Enter a base");
x=Integer.parseInt(br.readLine());
System.out.println("Enter a exponent");
y=Integer.parseInt(br.readLine());
while(y>0)
{
z=z*x;
y--;
}
System.out.println("The Power is .. "+z);
}
}

Sample Output :

Enter a base
2
Enter a exponent
3
The Power is .. 8

6. To find a square root of a number.

import java.io.*;
class sqrt
{
public static void main(String args[]) throws IOException
{
int x;
InputStreamReader is=new InputStreamReader(System.in);
BufferedReader br= new BufferedReader(is);
System.out.println("Enter a number");
x=Integer.parseInt(br.readLine());
Syste,.out.println("SQRT="+Math.sqrt(x));
}
}

Sample Output:

Enter a number
49
SQRT=7.0

7. Java Program to check Even or Odd number

import java.util.Scanner;

class B

{

public static void main(String args[])

  {

    int num;

    System.out.println("Enter an Integer number:");

  //The input provided by user is stored in num

    Scanner input = new Scanner(System.in);

    num = input.nextInt();

 /* If number is divisible by 2 then it's an even number

     * else odd number*/

    if ( num % 2 == 0 )

        System.out.println("Entered number is even");

     else

        System.out.println("Entered number is odd");

  }

}

Output :

Enter an Integer number :

12

Entered number is even

8. Example Java Program to check whether a given number is prime or not

import java.util.*;
public class B

{

    public static void main(String[] args) 

    {

        Scanner scanner = new Scanner(System.in);

        System.out.println("Please enter a number: ");

        int num = scanner.nextInt();

        

        B primeNum = new B();

        if ( primeNum.isPrime(num) ) {

            System.out.printf("\n Result: The number %d is Prime", num);

        } else {

            System.out.printf("\n Result: The number %d is not Prime", num);

        }

    }

    

    // Method to check whether the number is prime or not

    public boolean isPrime(int num) {

        if ( num < 2 ) return false;

        for (int i = 2; i <= Math.sqrt(num); i++) {

            if ( num % i == 0 ) {

                return false;

            }

        }

        return true;

    }

}

OUTPUT :

Please enter a number : 23

Result: The number 23 is Prime

9.  Write Java program to check if a number is Armstrong number or not?

class Armstrong{
 public static void main(String args[]){
  int num = Integer.parseInt(args[0]);
  int n = num; //use to check at last time
  int check=0,remainder;
  while(num > 0){
   remainder = num % 10;
   check = check + (int)Math.pow(remainder,3);
   num = num / 10;
  }
  if(check == n)
   System.out.println(n+" is an Armstrong Number");
  else
   System.out.println(n+" is not a Armstrong Number");
 }
}

Output :

Input - 153
  Output - 1^3 + 5^3 + 3^3 = 153, so it is Armstrong no.