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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
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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
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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