Java Program to calculate area of circle using SWITCH statement

//Program to calculate area of circle using SWITCH statement
import java.util.*;
class switch1
     {
public static void main(String args[])
      {
    float r,d,area;
    int n;
    System.out.println(" You want to calculate area of circle using");
    System.out.println(" 1.Radius \n 2.Diameter");
    System.out.println(" Enter your choice:");
    Scanner obj=new Scanner(System.in);
    n=obj.nextInt();
    switch(n)
      {
    case 1:
          {
        System.out.println(" Enter radius:");
        r=obj.nextFloat();       
        System.out.println(" Area of circle = "+3.14*2*r);
        break;
          }
    case 2:
          {
        System.out.println(" Enter diameter:");
        d=obj.nextFloat();       
        System.out.println(" Area of circle = "+3.14*d);
        break;
          }
    default:
        System.out.println(" Invalid choice ");
     }
       }
     }
A similar program to this
Java Program to calculate area of circle using if-else statement

Java Program to find word count in a given text

//Program to find word count in a given text

import java.util.*;
class wcount
     {
   public static void main(String args[])
      {
    String s;
    int i,w=1;
    System.out.println(" Enter text : ");
    Scanner obj=new Scanner(System.in);
    s=obj.nextLine();
    char a[]=s.toCharArray();
    if(a.length==0)
       w=0;
    else
      {
    for(i=0;i<a.length;i++)
       {
        if(a[i]==' '||a[i]=='\0')
            w++;
       }
      }
    System.out.println("\n Word count is : "+w);
    System.out.println();
     }
}

The Output will be similar to this

 when you don't enter anything

           

Java Program to find frequency count of letters in a given text

//Program to find frequency count of letters in a given text

import java.util.*;
class fcount
     {
   public static void main(String args[])
      {
    char ch;
    String s;
    int i,f=0;
    System.out.println(" Enter a string : ");
    Scanner obj=new Scanner(System.in);
    s=obj.nextLine();
    char a[]=s.toCharArray();
    System.out.println("Enter a character to find its frequency : ");
    ch=obj.next().charAt(0);
    for(i=0;i<a.length;i++)
       {
        if(ch==a[i])
            f++;
       }
    System.out.println("\n Frequency count of "+ch+" is : "+f);
    System.out.println();
     }
}

The Output will be similar to this

 when you enter a character which is not entered in the string

Similar program:-
Java Program to find word count in a given text



           

Java Program to check given string is palindrome (or) not.

//Program to check given string is palindrome (or) not.

import java.util.*;
class palindrome
     {
   public static void main(String args[])
      {
        String s;
    Scanner in=new Scanner(System.in);
    System.out.println(" Enter your text: ");
    s=in.nextLine();
    char a[]=s.toCharArray();//converting string to array.
        int i=0,is_palin=1,j=a.length;//j stores the length of array.
        for(i=0,j=j-1;i<j;i++,j--)
          {
           if(a[i]!=a[j])
             {
               is_palin=0;
               break;
             }
          }
    if(is_palin==1)
       {
        System.out.println("It is palindrome");
       }
    else
        {
          System.out.println(" It is not palindrome");
        }
      }
    }

The Output will be similar to this
   when you enter WELCOME and MADAM

Java Program to sort a list of names in Descending order

//Program to sort a list of names in Descending order

import java.util.*;
class Descendnames
     {
public static void main(String args[])
      {
    int n,i,j;
    System.out.println(" How many names you want to sort in Descending order:");
    Scanner obj=new Scanner(System.in);
    n=obj.nextInt();
    String temp,a[]=new String[n];//Declaring array of Strings
    Scanner obj1=new Scanner(System.in);
    System.out.println(" Enter names");
    for(i=0;i<n;i++)
        {
        a[i]=obj1.nextLine();
        }
    System.out.println(" Unsorted names : ");
    for(i=0;i<n;i++)
          {
        System.out.println(a[i]);
          }
    for (i = 0; i < n; i++)
            {
            for (j = i + 1; j < n; j++)
             {
                if (a[i].compareTo(a[j])<0) //compareTo() method is used for  comparing two //strings lexicographically.
                {
                    temp = a[i];
                    a[i] = a[j];
                    a[j] = temp;
                }
            }
        }
    System.out.println("\n Sorted names in Descending order ");
    for(i=0;i<n;i++)
          {
        System.out.println(a[i]);
          }
     System.out.println( );
      }
    }

The output will be similar to this

Java Program to sort a list of names in ascending order

//Program to sort a list of names in ascending order

import java.util.*;
class Ascendnames
     {
public static void main(String args[])
      {
    int n,i,j;
    System.out.println(" How many names you want to sort in Ascending order:");
    Scanner obj=new Scanner(System.in);
    n=obj.nextInt();
    String temp,a[]=new String[n];//Declaring array of Strings
    Scanner obj1=new Scanner(System.in);
    System.out.println(" Enter names");
    for(i=0;i<n;i++)
        {
        a[i]=obj1.nextLine();
        }
    System.out.println(" Unsorted names : ");
    for(i=0;i<n;i++)
          {
        System.out.println(a[i]);
          }
    for (i = 0; i < n; i++)
            {
            for (j = i + 1; j < n; j++)
             {
                if (a[i].compareTo(a[j])>0) //compareTo() method is used for comparing two //strings lexicographically.
                {
                    temp = a[i];
                    a[i] = a[j];
                    a[j] = temp;
                }
            }
        }
    System.out.println("\n Sorted names in ascending order ");
    for(i=0;i<n;i++)
          {
        System.out.println(a[i]);
          }
     System.out.println( );
      }

    }

The output will be similar to this:

Java Program to illustrate method overloading

//Program to illustrate method overloading
import java.util.*;
class overload
     {
 
     public static void print(int a,int b)
    {
      System.out.println("Printing int values");
      System.out.println("Before swapping ");
      System.out.println("\t a = "+a+" b = "+b);
      int temp;
      temp=a;
      a=b;
      b=temp;
      System.out.println("After swapping ");
      System.out.println("\t a = "+a+" b = "+b);
    }
    public static void print(char a,char b)
    {
      System.out.println("Printing char values");
      System.out.println("Before swapping ");
      System.out.println("\t a = "+a+" b = "+b);
      char temp;
      temp=a;
      a=b;
      b=temp;
      System.out.println("After swapping ");
      System.out.println("\t a = "+a+" b = "+b);
    }
    public static void print(double a,double b)
    {
      System.out.println("Printing real values");
      System.out.println("Before swapping ");
      System.out.println("\t a = "+a+" b = "+b);
      double temp;
      temp=a;
      a=b;
      b=temp;
      System.out.println("After swapping ");
      System.out.println("\t a = "+a+" b = "+b);
    }
       public static void main(String args[])
        {
      System.out.println(" ");
      print(10,20);
      print('X','Y');
      print(10.2,12.5);
        }
     }