javascript:数组中较大边的最接近的数字

function findClosestNumber(arr) {
  let max = -Infinity;
  let secondMax = -Infinity;

  // 找到数组中的最大值和次大值
  for (let num of arr) {
    if (num > max) {
      secondMax = max;
      max = num;
    } else if (num > secondMax) {
      secondMax = num;
    }
  }

  let closestNumber = arr[0];
  let minDiff = Infinity;

  // 找到最接近的数字
  for (let num of arr) {
    let diff = Math.abs(num - max);
    if (diff < minDiff) {
      minDiff = diff;
      closestNumber = num;
    }
  }

  return closestNumber;
}

// 示例用法
const arr = [1, 5, 9, 12, 15];
const closest = findClosestNumber(arr);
console.log(closest); // 输出：12