In the secret book of ACM, it’s said: “Glory for those who write short ICPC problems. May they live long, and never get Wrong Answers” . Everyone likes problems with short statements. Right? Let’s have five positive numbers: X1,X2,X3,X4,X5. We can fo…

剑指offer算法学习总结 节选剑指offer比较经典和巧妙的一些题目,以便复习使用.一部分题目给出了完整代码,一部分题目比较简单直接给出思路.但是不保证我说的思路都是正确的,个人对算法也不是特别在行,只不过这本书的算法多看了几遍多做了几遍多了点心得体会.于是想总结一下.如果有错误也希望能指出,谢谢. 具体代码可以参考我的GitHub仓库: https://github.com/h2pl/SwordToOffer 数论和数字规律 从1到n整数中1出现的次数 题目描述 求出1~13的整数中1出现的…

You are given two integer arrays nums1 and nums2 sorted in ascending order and an integer k. Define a pair (u,v) which consists of one element from the first array and one element from the second array. Find the k pairs (u1,v1),(u2,v2) ...(uk,vk) wit…

Cube digit pairs Each of the six faces on a cube has a different digit (0 to 9) written on it; the same is done to a second cube. By placing the two cubes side-by-side in different positions we can form a variety of 2-digit numbers. For example, the…

You are given two integer arrays nums1 and nums2 sorted in ascending order and an integer k. Define a pair (u,v) which consists of one element from the first array and one element from the second array. Find the k pairs (u1,v1),(u2,v2) ...(uk,vk) wit…

Pairs Forming LCM (LightOJ - 1236)[简单数论][质因数分解][算术基本定理](未完成) 标签: 入门讲座题解 数论 题目描述 Find the result of the following code: long long pairsFormLCM( int n ) { long long res = 0; for( int i = 1; i <= n; i++ ) for( int j = i; j <= n; j++ ) if( lcm(i, j) ==…

You are given two integer arrays nums1 and nums2 sorted in ascending order and an integer k. Define a pair (u,v) which consists of one element from the first array and one element from the second array. Find the k pairs (u1,v1),(u2,v2) ...(uk,vk) wit…

[BZOJ 2154]Crash的数字表格(莫比乌斯反演+数论分块) 题面 求 \[\sum_{i=1}^{n} \sum_{j=1}^{m} \mathrm{lcm}(i,j)\] 分析 \[\sum_{i=1}^{n} \sum_{j=1}^{m} \mathrm{lcm}(i,j)\] \[=\sum_{i=1}^{n} \sum_{j=1}^{m} \frac{i j}{\mathrm{gcd}(i, j)}\] \[=\sum_{g=1}^{n} \sum_{i=1}^{n/g} \s…

问题标签: Lua Table 迭代器;Lua Table 输出顺序; Lua Table 顺序输出;Lua Table 数字索引 字符串索引;Lua Table pairs; 问题背景: 使用pairs输出table时,其输出顺序与通常认知不相符. 例如使用pairs输出如下table T = { [] = ", [] = ", [] = ", [] = ", [] = ", [] = ", [] = ", [] = ",…

意甲冠军: 要求 小于或等于n号码 (0<=n <= 1e18)尾数的数的阶乘0数为偶数 思考:当然不是暴力,因此,从数论.尾数0数为偶数,然后,它将使N阶乘5电源是偶数.(二指数肯定少5指数),乞讨N.阶乘5该指数是N/5+ N/25+N/125. . .. 以530为例.尝试着将转化为5进制  即为 4110.那么5的指数 就是 411+41+4 (5进制)easy发现要使这个数是偶数.就是要使5进制奇数位的个数为偶数.依据刚才那个加法,能够看出,最后结果的5进制的末位就是411+41+4…