pub struct Solution;
剑指 Offer 42. 连续子数组的最大和 https://leetcode.cn/problems/lian-xu-zi-shu-zu-de-zui-da-he-lcof/
TypeId
self
Returns the argument unchanged.
Calls U::from(self).
U::from(self)
That is, this conversion is whatever the implementation of From<T> for U chooses to do.
From<T> for U