Searching Algorithms (linear search, binary search)

What optimization technique is demonstrated in this linear search variation?

function searchWithSentinel(arr, target) {
  const lastElement = arr[arr.length - 1];
  arr[arr.length - 1] = target;
  
  let i = 0;
  while(arr[i] !== target) i++;
  
  arr[arr.length - 1] = lastElement;
  if(i < arr.length - 1 || lastElement === target) return i;
  return -1;
}

Binary splitting
Sentinel value usage
This implements sentinel optimization by: 1) Temporarily replacing last element with target, 2) Eliminating bounds checking in loop, 3) Reducing number of comparisons, 4) Guaranteeing loop termination, 5) Restoring original array state after search, 6) Improving CPU branch prediction, 7) Common optimization in linear search, 8) Especially effective for unsuccessful searches.
Jump searching
Index tracking

Next Question (21/24)