java.util.Arrays

Program # 1

/*

                illustration of

                                Arrays.sort() method

                                Arrays.binarySearch() method

                both Arrays.sort() and Arrays.binarySearch()

                are static methods.

               

                before applying binarySearch() method on this array,

                you should first have the array sorted in non descending order.

               

*/

import java.util.Arrays;

import java.io.BufferedReader;

import java.io.InputStreamReader;

import java.io.IOException;

class Main

{

                public static void main(String args[])

                {

                                try

                                {

                                               

                                                System.out.println("Enter the number of elements of the array : ");

                                                BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

                                                int n=Integer.parseInt(br.readLine());

                                                int arr[]=new int[n];

                                               

                                                System.out.println("Enter the data of the array : ");

                                               

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

                                                                arr[i]=Integer.parseInt(br.readLine());

                                                               

                                                Arrays.sort(arr);

                                                printArray(arr);

                                               

                                                System.out.println("the index of 5 in the Array is : "+Arrays.binarySearch(arr,5));

                                }

                                catch(IOException e)

                                {

                                                System.out.println(e);

                                }

                                catch(NumberFormatException e)

                                {             

                                                System.out.println(e);

                                }

                }

               

                public static void printArray(int[]a)

                {

                                System.out.println("\nyour array is as follows :");

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

                                                System.out.println(a[i]);

                }

}

/*****************************************************************/

Program # 2

/*****************************************************************/

/*

                illustration of

                                Arrays.sort(int[]arr,int start,int end) method     

               

                the above function will sort the array

                starting from the index "start"

                and will sort the array till the index "end-1"

*/

import java.util.Arrays;

import java.io.BufferedReader;

import java.io.InputStreamReader;

import java.io.IOException;

class Main

{

                public static void main(String args[])

                {

                                try

                                {

                                               

                                                System.out.println("Enter the number of elements of the array : ");

                                                BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

                                                int n=Integer.parseInt(br.readLine());

                                                int arr[]=new int[n];

                                               

                                                System.out.println("Enter the data of the array : ");

                                               

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

                                                                arr[i]=Integer.parseInt(br.readLine());

                                                               

                                                System.out.print("Enter the index from where you want to start sorting  : ");

                                                int a=Integer.parseInt(br.readLine());

                                                System.out.print("Enter the index till which you want to sort the array : ");

                                                int b=Integer.parseInt(br.readLine());

                                               

                                                Arrays.sort(arr,a,b+1);

                                                printArray(arr);

                                }

                                catch(IOException e)

                                {

                                                System.out.println(e);

                                }

                                catch(NumberFormatException e) // due to Integer.parseInt()

                                {             

                                                System.out.println(e);

                                }

                }

               

                public static void printArray(int[]a)

                {

                                System.out.println("\nyour array is as follows :");

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

                                                System.out.println(a[i]);

                }

}