java simple binary search code example

Example 1: binary search java

binary search program in java.
public class BinarySearchExample
{
   public static void binarySearch(int[] arrNumbers, int start, int end, int keyElement)
   {
      int middle = (start + end) / 2;
      while(start <= end)
      {
         if(arrNumbers[middle] < keyElement)
         {
            start = middle + 1;
         }
         else if(arrNumbers[middle] == keyElement)
         {
            System.out.println("Element found at index: " + middle);
            break;
         }
         else
         {
            end = middle - 1;
         }
         middle = (start + end) / 2;
      }
      if(start > end)
      {
         System.out.println("Element not found!");
      }
   }
   public static void main(String[] args)
   {
      int[] arrNumbers = {14,15,16,17,18};
      int keyElement = 16;
      int end = arrNumbers.length - 1;
      binarySearch(arrNumbers, 0, end, keyElement);
   }
}

Example 2: binary search java

public int runBinarySearchRecursively(
  int[] sortedArray, int key, int low, int high) {
    int middle = (low + high) / 2;
        
    if (high < low) {
        return -1;
    }

    if (key == sortedArray[middle]) {
        return middle;
    } else if (key < sortedArray[middle]) {
        return runBinarySearchRecursively(
          sortedArray, key, low, middle - 1);
    } else {
        return runBinarySearchRecursively(
          sortedArray, key, middle + 1, high);
    }
}