编辑代码

let array = [1, 2, 3, 4, 5, 6, 7, 8, 9]
let find = 7
let left = 0
let right = array.length - 1
let count = 0

while (left <= right) {
    let mid = Math.floor((left + right) / 2);

    if (find > array[right] || find < array[left]) {
        alert("没有查找到这个数")
        break;
    }

    count++;
    if (array[mid] == find) {
        console.log("该数在这个数组中，查找了" + count + "次, 为第" + mid + "项");
        return 0
    } else if (array[mid] > find) {
        right = mid - 1
    } else {
        left = mid + 1
    }
}