121. Best Time to Buy and Sell Stock
Say you have an array for which the $i^{th}$ element is the price of a given stock on day i.
If you were only permitted to complete at most one transaction (i.e., buy one and sell ...
3.longest substring without repeating
Given a string, find the length of the longest substring without repeating characters.
Examples:
Given "abcabcbb", the answer is "abc", which the length is 3.
G...
93. Restore IP Address
Given a string containing only digits, restore it by returning all possible valid IP address combinations.
Example:
12Input: "25525511135"Output: ["255.255.11.135&qu...
语义分割中的度量标准
pixel accuracy (PA，像素精度)标记正确的像素占总像素的比例
$$PA=\frac{\sum_{i=1}^kp_{ii}}{\sum_{i=0}^k\sum_{j=0}^kp_{ij}}$$
mean pixel accuracy (MPA, 均像素精度)计算每个类中被正确分类像素的比例，然后平均
$$...
