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For the k-th number, we all should be very familiar with it. Of course,to kiki it is also simple. Now Kiki meets a very similar problem, kiki wants to 阅读全文
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杭州人称那些傻乎乎粘嗒嗒的人为62（音：laoer）。 杭州交通管理局经常会扩充一些的士车牌照，新近出来一个好消息，以后上牌照，不再含有不吉利的数字了，这样一来，就可以消除个别的士司机和乘客的心理障碍，更安全地服务大众。 不吉利的数字为所有含有4或62的号码。例如： 62315 73418 8891 阅读全文
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Jimmy writes down the decimal representations of all natural numbers between and including m and n, (m ≤ n). How many zeroes will he write down? Input 阅读全文
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题目链接： https://odzkskevi.qnssl.com/0c87453efec2747f8e8a573525fd42f9?v=1533651456 题解： 这是一道Trie+BFS的题目； 这是第二次写了 Orz 还是WA好几发； 这一题，我们可以用字典树存已有的单词，在存的时候，记录一 阅读全文
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Kelukin is a businessman. Every day, he travels around cities to do some business. On August 17th, in memory of a great man, citizens will read a book 阅读全文
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ACboy很喜欢玩一种战略游戏，在一个地图上，有N座城堡，每座城堡都有一定的宝物，在每次游戏中ACboy允许攻克M个城堡并获得里面的宝物。但由于地理位置原因，有些城堡不能直接攻克，要攻克这些城堡必须先攻克其他某一个特定的城堡。你能帮ACboy算出要获得尽量多的宝物应该攻克哪M个城堡吗？ Input每 阅读全文
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Genos recently installed the game Zuma on his phone. In Zuma there exists a line of n gemstones, the i-th of which has color ci. The goal of the game 阅读全文
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The multiplication puzzle is played with a row of cards, each containing a single positive integer. During the move player takes one card out of the r 阅读全文
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现在有n堆石子，第i堆有ai个石子。现在要把这些石子合并成一堆，每次只能合并相邻两个，每次合并的代价是两堆石子的总石子数。求合并所有石子的最小代价。 Input 第一行包含一个整数T（T<=50），表示数据组数。每组数据第一行包含一个整数n（2<=n<=100），表示石子的堆数。第二行包含n个正整数 阅读全文
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New labyrinth attraction is open in New Lostland amusement park. The labyrinth consists of n rooms connected by m passages. Each passage is colored in 阅读全文
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Ignatius再次被魔王抓走了(搞不懂他咋这么讨魔王喜欢)…… 这次魔王汲取了上次的教训，把Ignatius关在一个n*m的地牢里，并在地牢的某些地方安装了带锁的门，钥匙藏在地牢另外的某些地方。刚开始Ignatius被关在(sx,sy)的位置，离开地牢的门在(ex,ey)的位置。Ignatius每 阅读全文
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The Czech Technical University is rather old — you already know that it celebrates 300 years of its existence in 2007. Some of the university building 阅读全文
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A subsequence of a given sequence is the given sequence with some elements (possible none) left out. Given a sequence X = < x1, x2, ..., xm > another 阅读全文
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This is yet another problem dealing with regular bracket sequences. We should remind you that a bracket sequence is called regular, if by inserting «+ 阅读全文
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There is going to be a party to celebrate the 80-th Anniversary of the Ural State University. The University has a hierarchical structure of employees 阅读全文
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'Oh no, they've done it again', cries the chief designer at the Waferland chip factory. Once more the routing designers have screwed up completely, ma 阅读全文
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Farmer John's family pitches in with the chores during milking, doing all the chores as quickly as possible. At FJ's house, some chores cannot be star 阅读全文
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一：N条直线分割平面 假设，x条线能将平面分为f(x)份，这对于份f(n) 第n条线，和其他n-1条线都有交点时，增加量最大，为n; 则： f(n)=f(n-1)+n; 有f(0)=1；得到：n 条直线分割平面的数量最大为：f(n)=n*(n+1)/2 + 1; 二. “V” 形线分割平面 对于“V 阅读全文
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Disky and Sooma, two of the biggest mega minds of Bangladesh went to a far country. They ate, coded and wandered around, even in their holidays. They 阅读全文
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链接：http://acm.hdu.edu.cn/showproblem.php?pid=6331 Walking Plan Problem Description There are n intersections in Bytetown, connected with m one way str 阅读全文
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链接：http://acm.hdu.edu.cn/showproblem.php?pid=6325 Interstellar Travel Problem Description After trying hard for many years, Little Q has finally recei 阅读全文
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Little Q and Little T are playing a game on a tree. There are n vertices on the tree, labeled by 1,2,...,n , connected by n−1 bidirectional edges. The 阅读全文
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链接：http://acm.hdu.edu.cn/showproblem.php?pid=6322 Problem Description In number theory, Euler's totient function φ(n) counts the positive integers up 阅读全文
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有一棵由N个结点构成的树，每一条边上都有其对应的权值。现在给定起点，求从该点出发的一条路径（至少有一条边）使得这条路径上的权值之和最大，并输出这个最大值。 Input 第一行一个正整数T，代表数据组数。每组数据第一行两个正整数n(2<=n<=10^5),s(1<=s<=n)，分别表示树结点数目以及给 阅读全文
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链接：http://codeforces.com/contest/401/problem/D 题意：给出一个数字num和m，问通过重新排列num中的各位数字中有多少个数(mod m)=0,直接枚举全排列肯定不行，可以用状压dp来搞.. dp[S][k]表示选了num中的S且(mod m)=k的方案种 阅读全文