摘要：HihoCoder 1509 Given a sequence a[1..n], you need to calculate how many integers S satisfy the following conditions: (1). 0 ≤ S typedef long long ll; 阅读全文

摘要：CodeForces 1005D Polycarp likes numbers that are divisible by 3. He has a huge number s. Polycarp wants to cut from it the maximum number of numbers t 阅读全文

摘要：CodeForces 1006D You are given two strings a and b consisting of lowercase English letters, both of length n. The characters of both strings have indi 阅读全文