预处理即可 我们要找的是 (f[i] - f[j]) % k == i - j 移项可得 f[i] - i = f[j] - j 在 i - j <= k 的条件下 因此题目变成了,对于每个右端点,在它的左边 k - 1 个有多少个满足 f[i] - i = f[j] - j f[i] 是前缀和数组 AC_CODE #include <map> #include <iostream> #define LL long long using namespace std; cons…

D - Xor Sum 2 Time limit : 2sec / Memory limit : 1024MB Score : 500 points Problem Statement There is an integer sequence A of length N. Find the number of the pairs of integers l and r (1≤l≤r≤N) that satisfy the following condition: Al xor Al+1 xor …

题意:\(f(x,m)\)表示\(x\ mod\ m\),\(A_{1}=1\),而\(A_{n+1}=f(A^{2}_{n},M)\),求\(\sum^{n}_{i=1}A_{i}\). 题解:多算几个,会有一个循环节,直接模拟就好了. 代码: ll n,x,m; ll mp[N]; vector<ll> a; int main() { //ios::sync_with_stdio(false);cin.tie(0);cout.tie(0); scanf("%lld %lld %l…

A - Happy Birthday! Time limit : 2sec / Memory limit : 1000MB Score: 100 points Problem Statement E869120's and square1001's 16-th birthday is coming soon.Takahashi from AtCoder Kingdom gave them a round cake cut into 16 equal fan-shaped pieces. E869…

A - ABC/ARC Time limit : 2sec / Memory limit : 256MB Score : 100 points Problem Statement Smeke has decided to participate in AtCoder Beginner Contest (ABC) if his current rating is less than 1200, and participate in AtCoder Regular Contest (ARC) oth…

AtCoder Beginner Contest 137 F 数论鬼题(虽然不算特别数论) 希望你在浏览这篇题解前已经知道了费马小定理 利用用费马小定理构造函数\(g(x)=(x-i)^{P-1}\) \[x=i,g(x)=0\] \[x\ne i ,g(x)=1\] 则我们可以构造 \[f(x)=\sum^{i=0}_{P-1}(-a_i*(x-i)^{P-1}+a_i)\] 对于第\(i\)条式子当且仅当\(a_i=1 \ and \ x=i\)时取到\(1\) 代码写的比较奇怪 const…

人生第一场 AtCoder,纪念一下 话说年后的 AtCoder 比赛怎么这么少啊(大雾 AtCoder Beginner Contest 154 题解 A - Remaining Balls We have A balls with the string S written on each of them and B balls with the string T written on each of them. From these balls, Takahashi chooses one…

AtCoder Beginner Contest 177 题解 目录 AtCoder Beginner Contest 177 题解 A - Don't be late B - Substring C - Sum of product of pairs D - Friends E - Coprime F - I hate Shortest Path Problem A - Don't be late 问你能不能在时间\(T\)内用不高于\(S\)的速度走过\(D\)的路程,转化为判断\(ST\)…

比赛链接:https://atcoder.jp/contests/abc161/tasks AtCoder Beginner Contest 161 第一次打AtCoder的比赛,因为是日本的网站终于不用倒时差了233. A - ABC Swap 可以直接按照交换后的顺序输出. #include <bits/stdc++.h> using namespace std; int main() { int a,b,c; cin>>a>>b>>c; cout<…

小兔的话 欢迎大家在评论区留言哦~ AtCoder Beginner Contest 168 A - ∴ (Therefore) B - ... (Triple Dots) C - : (Colon) D - .. (Double Dots) E - ∙ (Bullet) 简单题意 小兔捕获了 \(N\) 条不同的沙丁鱼,第 \(i\) 条沙丁鱼的 美味程度 和 香味程度 分别是 \(A_i\) 和 \(B_i\) 她想在这些沙丁鱼中选择 一条 或者 多条 放入冷冻箱:但是必须保证沙丁鱼的选择是…