python二分查找带index

def binarysearch(l, value):
    def _binarysearch(_l, _value, beg, end):
        mid = (end + beg) // 2
        if beg == end:
            return -1
        if _value == _l[mid]:
            return mid
        elif _value < _l[mid]:
            return _binarysearch(_l, _value, beg, mid)
        else:
            return _binarysearch(_l, _value, mid + 1, end)

    return _binarysearch(l, value, 0, len(l))


l = [x * x for x in range(100) if x % 3 == 0]
print(l)
print(binarysearch(l, 900))
print(binarysearch(l, 0))
print(binarysearch(l, 9801))

 输出:

10
0
33