How to search element in Long Array using Index in Java?

Declaration :

public static int binarySearch(long[] a, int fromIndex, int toIndex, long key)

1	public static int binarySearch(long[] a, int fromIndex, int toIndex, long key)

Explanation :

Purpose	The java.util.Arrays.binarySearch(long[] a int fromIndex int toIndex long key) method searches a range of the specified array of longs for the specified value using the binary search algorithm. The range must be sorted before making this call.If it is not sorted the results are undefined.
Parameters	a ===> This is the array to be searched.
	fromIndex ===> This is the index of the first element (inclusive) to be searched.
	toIndex ===> This is the index of the last element (exclusive) to be searched.
	key ===> This is the value to be searched for.
Return Value	This method returns index of the search key if it is contained in the array else it returns (-(insertion point) - 1). The insertion point is the point at which the key would be inserted into the array; the index of the first element in the range greater than the key or toIndex if all elements in the range are less than the specified key.
Exception	IllegalArgumentException — if fromIndex > toIndex ,ArrayIndexOutOfBoundsException — if fromIndex < 0 or toIndex > a.length

Java Program : Example

Below example will explain java.util.Arrays.binarySearch() method.

package com.c4learn;
import java.util.Arrays;
public class ArrayDemo {
   public static void main(String[] args) {
		// Initialize the unsorted long array
		long arr[] = { 5000, 2000, 3000, 1000, 4000 };
		// Sort the long array
		Arrays.sort(arr);
		// Print the sorted long array list
		System.out.println("The sorted long array is:");
		for (long num : arr) {
			System.out.println("Array Element is " + num);
		}
		// Enter the value to be searched
		long Val = 3000;
		// Enter the range of index
		int retVal = Arrays.binarySearch(arr, 1, 5, Val);
		System.out.println("The index of element 3000 is : " + retVal);
	}
}

package com.c4learn;

import java.util.Arrays;

public class ArrayDemo {

public static void main(String[] args) {

// Initialize the unsorted long array

long arr[] = { 5000, 2000, 3000, 1000, 4000 };

// Sort the long array

Arrays.sort(arr);

// Print the sorted long array list

System.out.println("The sorted long array is:");

for (long num : arr) {

System.out.println("Array Element is " + num);

}

// Enter the value to be searched

long Val = 3000;

// Enter the range of index

int retVal = Arrays.binarySearch(arr, 1, 5, Val);

System.out.println("The index of element 3000 is : " + retVal);

}

Output of Program :

The sorted long array is:
Array Element is 1000
Array Element is 2000
Array Element is 3000
Array Element is 4000
Array Element is 5000
The index of element 3000 is : 2

The sorted long array is:

Array Element is 1000

Array Element is 2000

Array Element is 3000

Array Element is 4000

Array Element is 5000

The index of element 3000 is : 2

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