编辑代码

function binarySearch(arr, n, target){
    let l = 0;
    let r = n - 1;
    while(l <= r) {
        let mid = Math.floor((l + r) / 2);
        if(arr[mid] === target) {
            return mid
        }
        if(target < arr[mid]) {
            r = mid - 1
        }else {
            l = mid + 1
        }
    }
    return -1;
}

const arr = [1,3,5,6,34,44,56,76,99]
console.log(binarySearch(arr, arr.length, 44))