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// Recursive Binary Search
function binarySearch(bookCodes, targetCode) {
  return binarySearchRecursive(bookCodes, targetCode, 0, bookCodes.length - 1);
}
 
function binarySearchRecursive(bookCodes, targetCode, left, right) {
  // Base case: target not found
  if (left > right) {
    return -1;
  }
  
  // Calculate middle index
  const mid = Math.floor((left + right) / 2);
  
  // Check if we found the target
  if (bookCodes[mid] === targetCode) {
    return mid;
  }
  
  // If target is smaller, search in the left half
  if (bookCodes[mid] > targetCode) {
    return binarySearchRecursive(bookCodes, targetCode, left, mid - 1);
  }
  
  // If target is larger, search in the right half
  return binarySearchRecursive(bookCodes, targetCode, mid + 1, right);
}
 
// Iterative Binary Search (for comparison)
function binarySearchIterative(bookCodes, targetCode) {
  let left = 0;
  let right = bookCodes.length - 1;
  
  while (left <= right) {
    // Calculate middle index
    const mid = Math.floor((left + right) / 2);
    
    // Check if we found the target
    if (bookCodes[mid] === targetCode) {
      return mid;
    }
    
    // If target is smaller, search in the left half
    if (bookCodes[mid] > targetCode) {
      right = mid - 1;
    }
    // If target is larger, search in the right half
    else {
      left = mid + 1;
    }
  }
  
  // Target not found
  return -1;
}
 
// Test cases
const bookCodes1 = [1023, 1052, 1198, 1276, 1352, 1414, 1553];
const targetCode1 = 1276;
console.log(`Searching for book code ${targetCode1} in: [${bookCodes1}]`);
console.log(`Recursive Binary Search: Found at index ${binarySearch(bookCodes1, targetCode1)}`);
console.log(`Iterative Binary Search: Found at index ${binarySearchIterative(bookCodes1, targetCode1)}`);
 
const bookCodes2 = [2001, 2010, 2015, 2023, 2030];
const targetCode2 = 2020;
console.log(`\nSearching for book code ${targetCode2} in: [${bookCodes2}]`);
console.log(`Recursive Binary Search: Found at index ${binarySearch(bookCodes2, targetCode2)}`);
console.log(`Iterative Binary Search: Found at index ${binarySearchIterative(bookCodes2, targetCode2)}`);
 
const bookCodes3 = [3001, 3002, 3003, 3004, 3005];
const targetCode3 = 3001;
console.log(`\nSearching for book code ${targetCode3} in: [${bookCodes3}]`);
console.log(`Recursive Binary Search: Found at index ${binarySearch(bookCodes3, targetCode3)}`);
console.log(`Iterative Binary Search: Found at index ${binarySearchIterative(bookCodes3, targetCode3)}`);