James Pan

原题网址：https://leetcode.com/problems/count-primes/Description:Count the number of prime numbers less than a non-negative number, n.Credits:Special thanks to @mithmatt for adding this pro

原题网址：https://leetcode.com/problems/repeated-substring-pattern/Given a non-empty string check if it can be constructed by taking a substring of it and appending multiple copies of the substring t