如何根据数组的值组合数组的连续键？

function combineKeysByValue(arr) {
  const result = [];
  let start = 0;

  for (let i = 1; i < arr.length; i++) {
    if (arr[i] !== arr[i - 1]) {
      result.push([start, i - 1]);
      start = i;
    }
  }

  result.push([start, arr.length - 1]);

  return result;
}

const arr = [1, 1, 2, 3, 3, 3, 4, 5, 5];
const combinedKeys = combineKeysByValue(arr);
console.log(combinedKeys);

[[0, 1], [2, 4], [5, 6], [7, 8]]