【codeforces 757B】 Bash's Big Day
time limit per test2 seconds
memory limit per test512 megabytes
inputstandard input
outputstandard output
Bash has set out on a journey to become the greatest Pokemon master. To get his first Pokemon, he went to Professor Zulu’s Lab. Since Bash is Professor Zulu’s favourite student, Zulu allows him to take as many Pokemon from his lab as he pleases.
But Zulu warns him that a group of k > 1 Pokemon with strengths {s1, s2, s3, …, sk} tend to fight among each other if gcd(s1, s2, s3, …, sk) = 1 (see notes for gcd definition).
Bash, being smart, does not want his Pokemon to fight among each other. However, he also wants to maximize the number of Pokemon he takes from the lab. Can you help Bash find out the maximum number of Pokemon he can take?
Note: A Pokemon cannot fight with itself.
Input
The input consists of two lines.
The first line contains an integer n (1 ≤ n ≤ 105), the number of Pokemon in the lab.
The next line contains n space separated integers, where the i-th of them denotes si (1 ≤ si ≤ 105), the strength of the i-th Pokemon.
Output
Print single integer — the maximum number of Pokemons Bash can take.
Examples
input
3
2 3 4
output
2
input
5
2 3 4 6 7
output
3
Note
gcd (greatest common divisor) of positive integers set {a1, a2, …, an} is the maximum positive integer that divides all the integers {a1, a2, …, an}.
In the first sample, we can take Pokemons with strengths {2, 4} since gcd(2, 4) = 2.
In the second sample, we can take Pokemons with strengths {2, 4, 6}, and there is no larger group with gcd ≠ 1.
【题目链接】:http://codeforces.com/contest/757/problem/B
【题解】
枚举那个最大的组的gcd是什么(枚举那个gcd的质因子就好);
所以找出1..10W里面的所有质数S;
然后枚举以S的倍数为gcd的组的大小;
取最大值就好;
【完整代码】
#include <bits/stdc++.h>
using namespace std;
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define LL long long
#define rep1(i,a,b) for (int i = a;i <= b;i++)
#define rep2(i,a,b) for (int i = a;i >= b;i--)
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define rei(x) scanf("%d",&x)
#define rel(x) scanf("%I64d",&x)
typedef pair<int,int> pii;
typedef pair<LL,LL> pll;
const int dx[9] = {0,1,-1,0,0,-1,-1,1,1};
const int dy[9] = {0,0,0,-1,1,-1,1,-1,1};
const double pi = acos(-1.0);
const int MAXN = 1e5+100;
vector <int> v;
int n;
int a[MAXN];
int bo[MAXN];
bool is(int x)
{
int ma = sqrt(x);
rep1(i,2,ma)
if (x%i==0)
return false;
return true;
}
int main()
{
//freopen("F:\\rush.txt","r",stdin);
rep1(i,2,100000)
if (is(i))
v.pb(i);
rei(n);
rep1(i,1,n)
{
rei(a[i]);
bo[a[i]]++;
}
int len = v.size();
int ans = 1;
rep1(i,0,len-1)
{
int num = 0,x = v[i];
for (int now = x;now<=100000;now+=x)
num+=bo[now];
ans = max(ans,num);
}
printf("%d\n",ans);
return 0;
}
【codeforces 757B】 Bash's Big Day的更多相关文章
- 【Codeforces 757B】 Bash's big day
[题目链接] 点击打开链接 [算法] 若gcd(s1,s2,s3....sk) > 1, 则说明 : 一定存在一个整数d满足d|s1,d|s2,d|s3....,d|sk 因为我们要使|s|尽可 ...
- 【codeforces 757E】Bash Plays with Functions
[题目链接]:http://codeforces.com/problemset/problem/757/E [题意] 给你q个询问; 每个询问包含r和n; 让你输出f[r][n]; 这里f[0][n] ...
- 【codeforces 415D】Mashmokh and ACM(普通dp)
[codeforces 415D]Mashmokh and ACM 题意:美丽数列定义:对于数列中的每一个i都满足:arr[i+1]%arr[i]==0 输入n,k(1<=n,k<=200 ...
- 【codeforces 757A】Gotta Catch Em' All!
time limit per test1 second memory limit per test256 megabytes inputstandard input outputstandard ou ...
- 【codeforces 707E】Garlands
[题目链接]:http://codeforces.com/contest/707/problem/E [题意] 给你一个n*m的方阵; 里面有k个联通块; 这k个联通块,每个连通块里面都是灯; 给你q ...
- 【codeforces 707C】Pythagorean Triples
[题目链接]:http://codeforces.com/contest/707/problem/C [题意] 给你一个数字n; 问你这个数字是不是某个三角形的一条边; 如果是让你输出另外两条边的大小 ...
- 【codeforces 709D】Recover the String
[题目链接]:http://codeforces.com/problemset/problem/709/D [题意] 给你一个序列; 给出01子列和10子列和00子列以及11子列的个数; 然后让你输出 ...
- 【codeforces 709B】Checkpoints
[题目链接]:http://codeforces.com/contest/709/problem/B [题意] 让你从起点开始走过n-1个点(至少n-1个) 问你最少走多远; [题解] 肯定不多走啊; ...
- 【codeforces 709C】Letters Cyclic Shift
[题目链接]:http://codeforces.com/contest/709/problem/C [题意] 让你改变一个字符串的子集(连续的一段); ->这一段的每个字符的字母都变成之前的一 ...
随机推荐
- RFID的工作流程
工作流程 1.阅读器通过发射天线发送一定频率的射频信号, 2.当射频卡进入发射天线工作区域时产生感应电流,射频卡获得能量被激活: 3.射频卡将自身编码等信息通过卡内置发送天线发送出去 4.系统接收天线 ...
- 洛谷 P2677 超级书架 2
P2677 超级书架 2 题目描述 Farmer John最近为奶牛们的图书馆添置了一个巨大的书架,尽管它是如此的大,但它还是几乎瞬间就被各种各样的书塞满了.现在,只有书架的顶上还留有一点空间. 所有 ...
- 89.hash算法实现CSDN密码处理
初始化,数据的行数,hash链表结构体,存储头结点 #define _CRT_SECURE_NO_WARNINGS #include <stdio.h> #include <stdl ...
- spring mvc笔记
80214shuenjian224shuenjian@sina 北风网公开课课程大纲1.学习MVC框架的步骤2.Spring MVC运行机制3.演示Spring MVCAdd Maven suppor ...
- 使用Invoke解决多线程间的控件访问出错
// 按钮点击事件处理程序private void button1_Click(object sender, EventArgs e){ //创建新线程 Thread processorT ...
- [D3] Add hovercard
The way to add hovercard is Append a div with class 'hovercard' in the tick function, positioning th ...
- [ACM] POJ 1046 Color Me Less
Color Me Less Time Limit: 1000MS Memory Limit: 10000K Total Submissions: 30146 Accepted: 14634 D ...
- amazeui学习笔记--css(常用组件15)--CSS动画Animation
amazeui学习笔记--css(常用组件15)--CSS动画Animation 一.总结 1.css3动画封装:CSS3 动画封装,浏览器需支持 CSS3 动画. Class 描述 .am-anim ...
- SQL Server2008 Hierarchyid数据类型
以往我们在关系数据库中建立树状结构的时候,通常使用ID+ParentID来实现两条 纪录间的父子关系.但这种方式只能标示其相对位置.解决这类问题在SqlServer2005出现之前通常是采用游标来操作 ...
- 每天五个java相关面试题(3)
1. Servlet的生命周期是什么? 答: 第一次请求: 构造方法->init() -> service() -> doGet()/doPost() 以后的请求:service() ...