C. Median Smoothing Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/591/problem/C Description A schoolboy named Vasya loves reading books on programming and mathematics. He has recently read an encyclopedia article that des…

C. Median Smoothing   A schoolboy named Vasya loves reading books on programming and mathematics. He has recently read an encyclopedia article that described the method of median smoothing (or median filter) and its many applications in science and e…

分析: 三个01组合只有八种情况: 000 s001 s010 0011 s100 s101 1110 s111 s 可以看出只有010,101是不稳定的.其他都是稳定的,且连续地出现了1或0,标记为s. 考虑连续的不稳定串的,例子: 11010100   s        s  110100    s    s    1100 只有两种情况,两个边界是不同(11和00)或者相同(11或者00). 前者中间的不稳定串的长度是2*k,且经过k次将变成11110000,而后者的不稳定串的长度是2*k…

题目链接: http://codeforces.com/contest/664/problem/C 题解: 这题最关键的规律在于一位的有1989-1998(9-8),两位的有1999-2098(99-98),三位的有2099-3098(099-098),四位的有3099-13098(3099-3098) 所以关键字长度一样的会连续出现,1989+0代表一位的开始,1989+10代表两位的开始,1989+10+100代表三位的开始, 现在给你一个长度为len的标志,就可以找出该数位的起始位置198…

B. Rebranding The name of one small but proud corporation consists of n lowercase English letters. The Corporation has decided to try rebranding — an active marketing strategy, that includes a set of measures to change either the brand (both for the…

题目传送门 水 A - Wizards' Duel 题目都没看清就写了,1e-4精度WA了一次... /************************************************ * Author :Running_Time * Created Time :2015/10/25 16:27:20 * File Name :A.cpp ************************************************/ #include <cstdio> #i…

http://codeforces.com/problemset/problem/590/A: 在CF时没做出来,当时直接模拟,然后就超时喽. 题意是给你一个0 1串然后首位和末位固定不变,从第二项开始到倒数第二项,当前的a[i]=(a[i-1],a[i],a[i+1])三项排序后的中间项,比如连续3项为 1 0 1,那么中间的就变为1,然后题目让你输出达到稳定状态时所需的最小步数,不能的话输出-1. 无论给你啥数列,都能达到稳态.所以不可能输出-1: 还有一开始就稳定不变,或经过几次变换而稳定…

题意:一个数组,一次操作为:除首尾不变,其它的=它与前后数字的中位数,这样对数组重复几次后数组会稳定不变.问要操作几次,及最后的稳定数组. 挺难的题,参考了别人的代码和思路.总的来说就是找01010,010101这样的,分别变为00000,000111.不知道谁发现的将它和异或联系起来.比如对010101异或前一个元素为011111(记为数组b),数组b中连续的1全置0,如果是奇数那么连续的1的中间置1.结果是000100(数组c).再对数组c(除第一个元素)异或前一个元素,得到000111就是…

A. Wizards' Duel Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/591/problem/A Description Harry Potter and He-Who-Must-Not-Be-Named engaged in a fight to the death once again. This time they are located at opposite ends of…

E. Three States Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/591/problem/E Description The famous global economic crisis is approaching rapidly, so the states of Berman, Berance and Bertaly formed an alliance and allowed…