[传送门]https://nanti.jisuanke.com/t/31447 [题目大意]:有一个二分图,问能不能找到它的一个子图,使得这个子图中所有点的度数在区间[L,R]之内. [题解]首先我们分这几种情况讨论: (1)如果集合U,V中存在某个点,它的度数小于L,那么肯定就不满足题意,直接输出No.所以对任意i, degree[i] >= L (2)如果集合U,V中所有点的度数都在给定区间内,直接输出Yes. (3)如果集合U,V中存在某些点的度数大于R,则需要减少与它关联的边,直到它的度…
2018 ICPC 沈阳网络赛 Call of Accepted 题目描述:求一个算式的最大值与最小值. solution 按普通算式计算方法做,只不过要同时记住最大值和最小值而已. Convex Hull 题目描述:定义函数\(gay(x)\),若\(x\)是某个非\(1\)的数的平方的倍数,则\(gay(x)=0\),否则\(gay(x)=x^2\),求\(\sum_{num=1}^{n} ( \sum_{i=1}^{num} gay(x) ) mod p\) solution \[\sum…
[传送门]https://nanti.jisuanke.com/t/31452 [题目大意]:给定一个数字(最大可达10100),现在要求不超过它的最大超级质数.超级质数定义:对于一个数,把它看成数字序列 ,如果它的所有子序列形成的数都是质数,那么它就是超级质数. 比如说3137,它的子序列有3,1,7,31,33,37,313,317,137.....由于有一个子序列是33它不是质数,所有3137不是超级质数. [题解]注意,子序列和子串是不同的,子序列包含子串.子序列只要求相对顺序不变,而子…
[传送门]https://nanti.jisuanke.com/t/31458 [题目大意]有N个帧,每帧有K个动作特征,每个特征用一个向量表示(x,y).两个特征相同当且仅当他们在不同的帧中出现且向量的两个分量分别相等.求最多连续相同特征的个数? [题解]用一个map来维护帧中特征的信息,map中的键即读入的向量,因此用一个pair<int , int>表示,键的值也是一个pair,需要记录它当前已经连续了多少次,还需要记录它上一次出现的帧的位置.如果它上一帧没有出现过,那么它的连续次数就要…
A square-free integer is an integer which is indivisible by any square number except 11. For example, 6 = 2 \cdot 36=2⋅3 is square-free, but 12 = 2^2 \cdot 312=22⋅3 is not, because 2^222 is a square number. Some integers could be decomposed into prod…
ACM-ICPC 2018 南京赛区网络预赛 E题 题目链接: https://nanti.jisuanke.com/t/30994 Dlsj is competing in a contest with n (0 < n \le 20)n(0<n≤20) problems. And he knows the answer of all of these problems. However, he can submit ii-th problem if and only if he has s…
题目链接:https://nanti.jisuanke.com/t/30991 Feeling hungry, a cute hamster decides to order some take-away food (like fried chicken for only 3030 Yuan). However, his owner CXY thinks that take-away food is unhealthy and expensive. So she demands her hams…
There are N children in kindergarten. Miss Li bought them NNN candies. To make the process more interesting, Miss Li comes up with the rule: All the children line up according to their student number (1...N), and each time a child is invited, Miss Li…
God Water likes to eat meat, fish and chocolate very much, but unfortunately, the doctor tells him that some sequence of eating will make them poisonous. Every hour, God Water will eat one kind of food among meat, fish and chocolate. If there are 3 c…
2018 ICPC 徐州网络赛 A. Hard to prepare 题目描述:\(n\)个数围成一个环,每个数是\(0\)~\(2^k-1\),相邻两个数的同或值不为零,问方案数. solution 将环变成链,设\(f[i][0\)~\(2]\),分别表示与第一个数相同,与第一个数不同,与第一个数相同,与第一个数的反相同.然后\(dp\)即可. 时间复杂度:\(O(n)\) B. BE, GE or NE solution 根据题目描述\(dp\)即可. 时间复杂度:\(O(nm)\) C.…