1 First draw a state transition diagram using regular expressions,
https://leetcode-cn.com/problems/valid-number/solution/xiang-xi-tong-su-de-si-lu-fen-xi-duo-jie-fa-by-1-4/
1 First draw a state transition diagram using regular expressions,
https://leetcode-cn.com/problems/valid-number/solution/xiang-xi-tong-su-de-si-lu-fen-xi-duo-jie-fa-by-1-4/