使用while循环，如何求出从n到n的所有偶数的平均值？(Javascript)

function calculateAverage(n, m) {
  let count = 0;
  let sum = 0;

  while (n <= m) {
    if (n % 2 === 0) {
      sum += n;
      count++;
    }
    n += 2;
  }

  if (count !== 0) {
    const average = sum / count;
    return average;
  } else {
    return "No even numbers in the range.";
  }
}

// 示例调用
const n = 2;
const m = 10;
const average = calculateAverage(n, m);
console.log("平均值为：" + average);