算法图解1.2二分查找报TypeError: list indices must be integers or slices, not float解决方法

def binary_search(list, item):
    low = 0
    high = len(list) - 1

    while low <= high:
        mid = (low + high) / 2
        guess = list[mid]
        if guess == item:
            return guess
        if guess > item:
            high = mid - 1
        else:
            low = mid + 1
    return None


my_list = [1, 3, 5, 7, 9]

print(binary_search(my_list, 3))
print(binary_search(my_list, -1))

将以下这一行

mid = (low + high) / 2

改成

mid = int((low + high) / 2)

将其强转成整型。

因为列表索引必须是整型或切片

还有一种方式

就是

mid = low + (high - low) / 2