一.题意 No response.T_T 二.思路 分$n$为奇数或者偶数讨论. 如果$n$是奇数,列出不等式组:$r_1+r_2=d_{1},r_2+r_3=d_{2},r_3+r_4=d_{3},\cdots,r_{n-1}+r_n=d_{n-1},r_n+r_1=d_n$,可以解出,$r_1=\frac{d_{1}+d_{3}+d_{5}+\cdots-d_{2}-d_{4}-\cdots}{2}$,然后再用上述式子依次算出$r_2$至$r_n$.最后判断$r_1$至$r_n$中是否存在负…

链接在这:http://bak.vjudge.net/contest/132442#overview. A题,给出a,b和n,初始的集合中有a和b,每次都可以从集合中选择不同的两个,相加或者相减,得到一个新的数,如果在1~n内的话就放入集合中,并算一次操作,谁先不能操作(所有新数已经存在于集合内的话就不能进行操作)者输.问谁会赢. 可以得到的数字为k*gcd(a,b),那么只要算出在1~n的范围内存在多少个这样的数字,判断一下奇偶性即可. B题,给出n个字符串,问最大的满足条件的字符串的位置,条…

House Building Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 262144/262144 K (Java/Others)Total Submission(s): 145    Accepted Submission(s): 123 Problem Description Have you ever played the video game Minecraft? This game has been one of t…

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Rebuild Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 262144/262144 K (Java/Others)Total Submission(s): 446    Accepted Submission(s): 113 Problem Description Archaeologists find ruins of Ancient ACM Civilization, and they want to rebuild i…