类似墨墨的等式 设f[2][j][k]表示a[i].c是否和当前颜色相同,到当前枚举到的颜色为止,颜色数为j,对mnv取模为k的最小数 这是个无限循环背包,用spfa优化 #include<cstdio> #include<iostream> #include<cstring> #include<cstdlib> #include<algorithm> #include<cmath> #include<map> using…

CodeChef-LECOINS Little Elephant and Colored Coins Little Elephant and Colored Coins The Little Elephant from the Zoo of Lviv very likes coins. But most of all he likes colored coins. He has N types of coins, numbered from 1 to N, inclusive. The coin…

The Little Elephant likes permutations. This time he has a permutation A[1], A[2], ..., A[N] of numbers 1, 2, ...,N. He calls a permutation A good, if the number of its inversions is equal to the number of its local inversions. The number of inversio…

https://www.codechef.com/FEB14/problems/LEMOVIE 题意: 对于一个序列,定义其“激动值”为序列中严格大于前面所有数的元素的个数.给定n个数p1;,p2... pn,求这n个数的所有排列中,激动值不超过k的个数.$1 k \le n \le 200,1 \le pi \le 200$ 这种题有一个很神的想法: 把排列按某种顺序往里插入,使得后不会影响前 对于本题,先离散化去重后,从大到小插入,后插入的元素不会影响已经插入的元素严格大于前面所有数 $f[…

https://www.codechef.com/problems/LEMOUSE 题意: 有一个n *m的网格.有一头大象,初始时在(1,1),要移动到(n,m),每次只能向右或者向下走.有些格子中有老鼠,如果大象所在的格子和某个有老鼠的格子的曼哈顿距离$\e$1,大象就会被那只老鼠吓到.求一条移动路径,使得吓到过大象的老鼠数量最少.n;m $\le$100. 开始刷济南集训hzc的课件啦! 最简单的一道$DP$ 一只老鼠只会吓大象一次$f[i][j][0/1]$记录从左还是上走来的,转移时讨…

The Little Elephant from the Zoo of Lviv currently is on the military mission. There are N enemy buildings placed in a row and numbered from left to right strating from 0. Each building i (except the first and the last) has exactly two adjacent build…

Given an array A1,A2...AN, you have to print the size of the largest contiguous subarray such that LCM of all integers in that subarray is equal to the product of all integers in that subarray. Formally, For a subarray Ai,Ai+1...Aj where 1 ≤ i < j ≤…

难度 \(hard\) 题意 \(3\times n\)的方格,前两行已分别填入\(n-\)排列,要求求第三行填入\(n-\)排列,使得每行每列数不重复的方案数(数据保证前两行合法)\(n\le 1000\) 做法 建立二部图\(G\):左部分为位置,右部分为数字,边为可行 则转换为求二部图完美匹配方案数 考虑容斥,\(G\)的补图为\(G'\),其是一个性质很好的二部图:每个左节点恰好连出两条边 设\(F(x)\)为\(K_{n,n}\)完美匹配,恰好用到\(G'\)的\(x\)条边,\(\v…

原文链接:https://github.com/ethereum/wiki/wiki/White-Paper 当中本聪在2009年1月启动比特币区块链时,他同时向世界引入了两种未经测试的革命性的新概念.第一种就是比特币(bitcoin),一种去中心化的点对点的网上货币,在没有任何资产担保.内在价值或者中心发行者的情况下维持着价值.到目前为止,比特币已经吸引了大量的公众注意力, 就政治方面而言它是一种没有中央银行的货币并且有着剧烈的价格波动.然而,中本聪的伟大试验还有与比特币同等重要的一部分:基于…

https://github.com/ethereum/wiki/wiki/White-Paper White Paper EditNew Page James Ray edited this page on 4 Mar · 174 revisions A Next-Generation Smart Contract and Decentralized Application Platform An introductory paper to Ethereum, introduced befor…