How to search element in Long Array using Binary Search in Java?

Declaration :

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

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

Explanation :

Purpose	The java.util.Arrays.binarySearch(long[] a long key) method searches the specified array of longs for the specified value using the binary search algorithm.The array 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.
	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 greater than the key or a.length if all elements in the array are less than the specified key.
Exception	NA

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 unsorted long array
		long arr[] = { 500, 200, 300, 100, 400 };
		// Sorting array
		Arrays.sort(arr);
		// Printing the sorted long array
		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 = 400;
		int retVal = Arrays.binarySearch(arr, Val);
		System.out.println("The index of element 400 is : " + retVal);
	}
}

package com.c4learn;

import java.util.Arrays;

public class ArrayDemo {

public static void main(String[] args) {

// Initialize unsorted long array

long arr[] = { 500, 200, 300, 100, 400 };

// Sorting array

Arrays.sort(arr);

// Printing the sorted long array

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 = 400;

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

System.out.println("The index of element 400 is : " + retVal);

}

Output of Program :

The sorted long array is:
Array Element is 100
Array Element is 200
Array Element is 300
Array Element is 400
Array Element is 500
The index of element 400 is : 3

The sorted long array is:

Array Element is 100

Array Element is 200

Array Element is 300

Array Element is 400

Array Element is 500

The index of element 400 is : 3

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