Java: Find a specified element in a given array of elements using Binary Search

Last update on March 13 2025 09:04:48 (UTC/GMT +8 hours)

Write a Java program to find a specified element in a given array of elements using Binary Search.

Sample Solution:

Java Code:

public class Main {
     public static int binarySearch(int[] nums, int flag) {
        int hi_num = nums.length - 1;
        int lo_num = 0;
        while (hi_num >= lo_num) {
            int guess = (lo_num + hi_num) >>> 1;   
            if (nums[guess] > flag) {
                hi_num = guess - 1;
            } else if (nums[guess] < flag) {
                lo_num = guess + 1;
            } else {
                return guess;
            }
        }
        return -1;
    }
 
    public static void main(String[] args) {
        int[] nums = {1, 5, 6, 7, 8, 11};
        int search_num = 7;
        int index = binarySearch(nums, search_num);
        if (index == -1) {
            System.out.println(search_num + " is not in the array");
        } else {
            System.out.println(search_num + " is at index " + index);
        }
    }
}

Sample Output:

7 is at index 3

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Java program to implement binary search on an array of custom objects using a Comparator to determine order.
• Write a Java program to modify binary search to return the index of the first occurrence when duplicates exist.
• Write a Java program to perform binary search on a rotated sorted array without restoring the original order.
• Write a Java program to extend binary search to work on an array with missing values, returning the index of the closest match.

Java Code Editor:

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