随笔分类 - 数学
摘要：Opposite to Grisha's nice behavior, Oleg, though he has an entire year at his disposal, didn't manage to learn how to solve number theory problems in
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摘要：题意翻译 Description 有一个长为nnn ，宽为mmm 的鱼缸，还有一个边长为rrr 的正方形渔网。你可以往鱼缸里放kkk 条鱼，问用渔网随机在浴缸里捞鱼的最大期望是多少。不懂什么是期望的自己去百度 Input 一行4个正整数代表n,m,r,kn, m, r, kn,m,r,k Outpu
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摘要：Mahmoud has an array a consisting of n integers. He asked Ehab to find another array b of the same length such that: b is lexicographically greater th
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摘要：题意翻译 给你一串数列a.对于一个质数p,定义函数f(p)=a数列中能被p整除的数的个数.给出m组询问l,r,询问[l,r]区间内所有素数p的f(p)之和. 题目描述 Recently, the bear started studying data structures and faced the
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摘要：https://www.luogu.org/problemnew/show/P4942 上面为原题地址； 引理： 一个数字除以9的余数等于它的各位数字之和除以9的余数 那么我们将其各个数字加起来%9即可； 当然用等差数列公式更快；
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摘要：Try guessing the statement from this picture: You are given a non-negative integer d . You have to find two non-negative real numbers a and b such tha
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