#include <bits/stdc++.h> #define ll long long #define fi first #define se second #define pb push_back #define me memset #define rep(a,b,c) for(int a=b;a<=c;++a) #define per(a,b,c) for(int a=b;a>=c;--a) const int N = 1e6 + 10; const int mod = 1e9 + 7; co...
Product 1 Modulo N 来源:https://codeforces.com/problemset/problem/1514/C 标签:【数学】【贪心】【思维】 题目简述 给定一个数n,找到[0,1,2,...,n-1]最长的子序列使子序列中1所有的数的乘积余n等于1。(b是a的子序列即
Samples 输入数据 1 2 2 2 7 Copy 输出数据 1 1 2 Copy Note The multiplicative order of a numberamoduloQ , is the smallest natural numberxsuch thataxmodQ = 1. For example, .
对于奇数n,自身平方对n取模的个数为num=2l,l是对n进行质因数分解后不同的质因数个数。 一、当奇数n为质数的时候,num=2,此时我们可以证明威尔逊定理(当且仅当p为素数的时候,(p-1)!≡-1(mod p)),此时A中元素的乘积对n取模为-1。 二、当奇数n不为质数时,num可以被4整除,因此A中元素的乘积对n取模...
https://codeforces.ml/contest/1514/problem/C Now you get Baby Ehab's first words: "Given an integer n, find the longest subsequence of [1,2,…,n−1] whose product is 1 modulo n." Please solve the problem. A sequence b is a subsequence of an array a if b can be obtained from...