Lngxling的博客

SumdivTime Limit: 1000MS Memory Limit: 30000KTotal Submissions: 25199 Accepted: 6244DescriptionConsider two natural numbers A and B. Let S be the sum of all natural divisors of A^B. Determine S modulo...

题意：求最小的n的阶乘使得阶乘的末尾有q个0思路：阶乘末尾0的个数，即含有的5的倍数，求一次是log的复杂度，再二分一下#include <iostream>#include <cstdio>#include <algorithm>#include <cstring>#include <queue>#inclu...

题意：给定一个矩形的面积和最短边长，边长都是正整数，问矩形有多少种可能的形状思路：面积的所有因子的个数/2就是所有的x*y=s的对数，用算术基本定理求出所有的因子个数，然后减掉小于最短边长的部分一是要特判0的情况，二是要用longlong#include <bits/stdc++.h>#define ll long longusing namespace std;...

题意：给定n个数，对每个数求出一个数使得这个数的欧拉函数值大于这个数，求这些数的和思路：素数的欧拉值是最大的，满足题意的数一定是素数欧拉筛得到1e6内的所有素数，二分查找每个输入数的位置，相加即可#include <iostream>#include <cstdio>#include <algorithm>#include <cst...

A New Change ProblemTime Limit: 5000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 1610    Accepted Submission(s): 1024Problem DescriptionNow given two kinds o...

The BalanceTime Limit: 5000MS Memory Limit: 65536KTotal Submissions: 8159 Accepted: 3560DescriptionMs. Iyo Kiffa-Australis has a balance and only two kinds of weights to measure a dose of medicine. Fo...

Fermat vs. PythagorasTime Limit: 2000MS Memory Limit: 10000KTotal Submissions: 1651 Accepted: 965DescriptionComputer generated and assisted proofs and verification occupy a small niche in the realm of...

Sticks and Right TriangleTime Limit: 12000/4000 MS (Java/Others)    Memory Limit: 65535/65536 K (Java/Others)Total Submission(s): 793    Accepted Submission(s): 314Problem DescriptionWe have a stick w...

Prime DistanceTime Limit: 1000MS Memory Limit: 65536KTotal Submissions: 20935 Accepted: 5629DescriptionThe branch of mathematics called number theory is about properties of numbers. One of the areas t...

题意：数n可以写成a*b的形式，使得a和b的所有因子都不是平方数，问前n个数，每个数可以拆分的方法数的和。思路：就不该去oeis的，oeis出来莫比乌斯，需要每个数所有因子的莫比乌斯乘积，是在给定时间内处理不了的由算术基本定理，每个数都可以写成素数幂乘积的形式，x=p1^k1*p2^k2*p3^k3...pn^kn那么由题意，如果存在k大于3，这个数就没办法拆分如果k=2，...