随笔分类 - 题库—POJ
摘要:题意 "题目链接" 给出平面上n个点的坐标。你需要建一个围墙,把所有的点围在里面,且围墙距所有点的距离不小于l。求围墙的最小长度。 $n \leqslant 10^5$ Sol 首先考虑如果没有l的限制,那么显然就是凸包的长度。 现在了距离的限制,那么显然原来建在凸包上的围墙要向外移动$l$的距离,
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摘要:题意 "题目链接" 给定n条线段,确定是否存在一条直线,使得这n条线段在这条直线上的投影具有公共点。 n include include using namespace std; const int MAXN = 1001; const double eps = 1e 10; int N; stru
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摘要:题意 "题目链接" $T$组数据,给出$n$个点的度数,问是否可以构造出一个简单图 Sol Havel–Hakimi定理: 给定一串有限多个非负整数组成的序列,是否存在一个简单图使得其度数列恰为这个序列。 令$S=(d_1,d_2,\dots,d_n)$为有限多个非负整数组成的非递增序列。 S可简单
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摘要:题意 题目链接 给出$n \times n$的矩阵$A$,求$\sum_{i = 1}^k A^i $,每个元素对$m$取模 Sol 考虑直接分治 当$k$为奇数时 $\sum_{i = 1}^k A^i = \sum_{i = 1}^{k / 2 + 1} A^i + A^{k / 2 + 1}(
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摘要:题意 题目链接 给出$n$个点,求出一个点使得到各个点的距离之和最小,距离为欧几里得距离 Sol 模拟退火真是玄学,我退了一上午,最后把exp函数去了就A了。 后来改了改,发现是大小符号的问题。。 但是 这样是对的。 然后把RAND_MAX除过去就错了。。 需要改大小号才行。真是玄学。。。
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摘要:题意 给出区间$[A, B]$,求出区间内的数转成二进制后$0$比$1$多的数的个数 $1 \leqslant A, B \leqslant 2,000,000,000$ Sol 比较zz的数位dp 直接在二进制下dp就好 $f[i][ze][on]$表示第$i$位,填了$ze$个$0$,$on$个
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摘要:题意 抄袭自https://www.cnblogs.com/Paul-Guderian/p/7624039.html 输入n,s表示这里存在n种漏洞和s个系统(0<n,s<=1000)。工程师可以花费一天去找出一个漏洞——这个漏洞可以是以前出现过的种类,也可能是未曾出现过的种类,同时,这个漏洞出现在
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摘要:题意 开始时$p = 1$,每次可以乘$2 - 9$,第一个使得$p \geqslant n$的人赢 问先手是否必胜 $1 <n <4294967295$ Sol 认真的推理一波。 若当前的数为$\frac{n}{9} \leqslant x \leqslant n$,则先手必胜 若当前的数为$\f
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摘要:Time Limit: 1000MS Memory Limit: 10000K Total Submissions: 9359 Accepted: 3862 Description Beads of red, blue or green colors are connected together i
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摘要:Time Limit: 2000MS Memory Limit: 65536K Total Submissions: 11654 Accepted: 3756 Description Beads of N colors are connected together into a circular n
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摘要:Time Limit: 1000MS Memory Limit: 30000K Total Submissions: 33462 Accepted: 11124 Description A musical melody is represented as a sequence of N (1<=N<
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摘要:Time Limit: 3000MS Memory Limit: 65536K Total Submissions: 56162 Accepted: 23370 Description Given two strings a and b we define a*b to be their conca
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摘要:Time Limit: 3000MS Memory Limit: 10000K Total Submissions: 4901 Accepted: 2765 Description Once upon a time there was a famous actress. As you may exp
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摘要:Time Limit: 1000MS Memory Limit: 10000K Total Submissions: 9078 Accepted: 3515 Description A supermarket in Tehran is open 24 hours a day every day an
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摘要:Time Limit: 2000MS Memory Limit: 65536K Total Submissions: 28416 Accepted: 10966 Description You are given n closed, integer intervals [ai, bi] and n
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摘要:Time Limit: 2000MS Memory Limit: 65536K Total Submissions: 11049 Accepted: 3767 Special Judge Description John is the only priest in his town. Septemb
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摘要:Time Limit: 1000MS Memory Limit: 131072K Total Submissions: 10870 Accepted: 3988 Description liympanda, one of Ikki’s friend, likes playing games with
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摘要:Network Time Limit: 5000MS Memory Limit: 65536K Total Submissions: 10969 Accepted: 4096 Description A network administrator manages a large network. T
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摘要:Time Limit: 7000MS Memory Limit: 65536K Total Submissions: 13954 Accepted: 4673 Description Being a knight is a very attractive career: searching for
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摘要:Time Limit: 1000MS Memory Limit: 10000K Total Submissions: 9762 Accepted: 4397 Description Consider the two networks shown below. Assuming that data m
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