C++, binary search recursive

Binary search is a commonly used algorithm in computer science for searching for a specific value in a sorted array. It follows a divide-and-conquer approach, repeatedly dividing the search space in half until the target value is found or the search space is empty.

Here is an explanation of each step of the binary search recursive algorithm in C++:

  1. Start with a sorted array and the target value to search for.
  2. Define a recursive function, let's call it "binarySearchRecursive", that takes the array, the starting index, the ending index, and the target value as parameters.
  3. Calculate the middle index of the search space by adding the starting and ending indices and dividing by 2. Let's call this middle index "mid".
  4. Check if the middle element of the array is equal to the target value.
  5. If it is, return the index of the middle element as the result.
  6. If it is not, continue to the next step.
  7. Check if the starting index is greater than the ending index.
  8. If it is, return -1 as the result, indicating that the target value was not found in the array.
  9. If it is not, continue to the next step.
  10. Check if the middle element of the array is greater than the target value.
  11. If it is, recursively call the "binarySearchRecursive" function with the same array, starting index, and "mid - 1" as the ending index.
  12. If it is not, recursively call the "binarySearchRecursive" function with the same array, "mid + 1" as the starting index, and the same ending index.
  13. Repeat steps 3 to 6 until the target value is found or the search space is empty.
  14. Once the recursive calls are completed and the target value is not found, return -1 as the result, indicating that the target value was not found in the array.

This recursive binary search algorithm works by continually dividing the search space in half until the target value is found or the search space is empty. It eliminates half of the remaining search space in each recursive call, making it efficient for searching large sorted arrays.