算法编程题-二分查找

def BinarySearch(L,K):
    L_s = sorted(L)
    left, right = 0, len(L)-1
    while(L_s[left]<L_s[right]):
        print(left,right)
        mid = (left+right)//2
        if L_s[mid]>K:
            right = mid
        elif L_s[mid]<K:
            left=mid+1
        else:
            return("index is %d",L.index(K))
    return ("do not have %d",K)