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题目链接 Problem Description There are $$$n$$$ intersections in Bytetown, connected with $$$m$$$ one way streets. Little $$$Q$$$ likes sport walking very 阅读全文
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题目链接 Problem Description Chiaki is interested in an infinite sequence $$$a_1,a_2,a_3,...,$$$ which is defined as follows: $$$a_n= \begin{cases} 1, & \ 阅读全文
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题目链接 Problem Description In a galaxy far, far away, there are two integer sequence a and b of length n. b is a static permutation of 1 to n. Initially 阅读全文
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题目链接 Problem Description Chiaki has an array of n positive integers. You are told some facts about the array: for every two elements $$$a_i$$$ and $$$ 阅读全文
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题目链接 Problem Statement There are M chairs arranged in a line. The coordinate of the i-th chair ($$$1≤i≤M$$$) is $$$i$$$.N people of the Takahashi clan 阅读全文
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D. Fair time limit per test 2 seconds memory limit per test 512 megabytes input standard input output standard output Some company is going to hold a 阅读全文
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D. Buy a Ticket time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Musicians of a popular b 阅读全文
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C. Constructing Tests time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Let's denote a m-fr 阅读全文
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C. Useful Decomposition time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Ramesses knows a 阅读全文
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题目描述 给出四堆石子，石子数分别为a,b,c,d。规定每次只能从堆顶取走石子，问取走所有石子的方案数。 输入描述: 在一行内读入四个由空格分隔的整数a,b,c,d， 输入均为不超过500的正整数 输出描述: 输出一个整数表示答案，答案对109+7取模 示例1 输入 3 5 4 2 输出 25225 阅读全文