Video Cards
1 second
256 megabytes
standard input
standard output
Little Vlad is fond of popular computer game Bota-2. Recently, the developers announced the new add-on named Bota-3. Of course, Vlad immediately bought only to find out his computer is too old for the new game and needs to be updated.
There are n video cards in the shop, the power of the i-th video card is equal to integer value ai. As Vlad wants to be sure the new game will work he wants to buy not one, but several video cards and unite their powers using the cutting-edge technology. To use this technology one of the cards is chosen as the leading one and other video cards are attached to it as secondary. For this new technology to work it's required that the power of each of the secondary video cards is divisible by the power of the leading video card. In order to achieve that the power of any secondary video card can be reduced to any integer value less or equal than the current power. However, the power of the leading video card should remain unchanged, i.e. it can't be reduced.
Vlad has an infinite amount of money so he can buy any set of video cards. Help him determine which video cards he should buy such that after picking the leading video card and may be reducing some powers of others to make them work together he will get the maximum total value of video power.
The first line of the input contains a single integer n (1 ≤ n ≤ 200 000) — the number of video cards in the shop.
The second line contains n integers a1, a2, ..., an (1 ≤ ai ≤ 200 000) — powers of video cards.
The only line of the output should contain one integer value — the maximum possible total power of video cards working together.
4
3 2 15 9
27
4
8 2 2 7
18
In the first sample, it would be optimal to buy video cards with powers 3, 15 and 9. The video card with power 3 should be chosen as the leading one and all other video cards will be compatible with it. Thus, the total power would be 3 + 15 + 9 = 27. If he buys all the video cards and pick the one with the power 2 as the leading, the powers of all other video cards should be reduced by 1, thus the total power would be 2 + 2 + 14 + 8 = 26, that is less than 27. Please note, that it's not allowed to reduce the power of the leading video card, i.e. one can't get the total power 3 + 1 + 15 + 9 = 28.
In the second sample, the optimal answer is to buy all video cards and pick the one with the power 2 as the leading. The video card with the power 7 needs it power to be reduced down to 6. The total power would be 8 + 2 + 2 + 6 = 18.
分析:从小到大枚举每个数的倍数即可;
代码:
#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <algorithm>
#include <climits>
#include <cstring>
#include <string>
#include <set>
#include <map>
#include <queue>
#include <stack>
#include <vector>
#include <list>
#define rep(i,m,n) for(i=m;i<=n;i++)
#define rsp(it,s) for(set<int>::iterator it=s.begin();it!=s.end();it++)
#define mod 1000000007
#define inf 0x3f3f3f3f
#define llinf 0x3f3f3f3f3f3f3f3fLL
#define vi vector<int>
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define ll long long
#define pi acos(-1.0)
#define pii pair<ll,int>
#define Lson L, mid, ls[rt]
#define Rson mid+1, R, rs[rt]
#define sys system("pause")
const int maxn=4e5+;
using namespace std;
ll gcd(ll p,ll q){return q==?p:gcd(q,p%q);}
ll qpow(ll p,ll q){ll f=;while(q){if(q&)f=f*p;p=p*p;q>>=;}return f;}
inline ll read()
{
ll x=;int f=;char ch=getchar();
while(ch<''||ch>''){if(ch=='-')f=-;ch=getchar();}
while(ch>=''&&ch<=''){x=x*+ch-'';ch=getchar();}
return x*f;
}
int n,m,k,t,a[maxn],b[maxn];
ll ans,now;
set<int>p;
int main()
{
int i,j;
scanf("%d",&n);
rep(i,,n)scanf("%d",&a[i]),b[a[i]]++,p.insert(a[i]);
sort(a+,a+n+);
rep(i,,*a[n])b[i]+=b[i-];
for(int x:p)
{
now=0LL;
for(j=;(ll)x*(j-)<=a[n];j++)
{
now+=(ll)(b[x*j-]-b[x*(j-)-])*((ll)x*(j-));
}
ans=max(ans,now);
}
printf("%lld\n",ans);
//system("Pause");
return ;
}
Video Cards的更多相关文章
- Codeforces Round #376 (Div. 2) F. Video Cards 数学,前缀和
F. Video Cards time limit per test 1 second memory limit per test 256 megabytes input standard input ...
- Codeforces Round #376 (Div. 2) F. Video Cards —— 前缀和 & 后缀和
题目链接:http://codeforces.com/contest/731/problem/F F. Video Cards time limit per test 1 second memory ...
- 【19.05%】【codeforces 731F】 Video Cards
time limit per test1 second memory limit per test256 megabytes inputstandard input outputstandard ou ...
- Codeforces 731 F. Video Cards(前缀和)
Codeforces 731 F. Video Cards 题目大意:给一组数,从中选一个数作lead,要求其他所有数减少为其倍数,再求和.问所求和的最大值. 思路:统计每个数字出现的个数,再做前缀和 ...
- Codeforces Round #376 (Div. 2)F. Video Cards(前缀和)
题目链接:http://codeforces.com/contest/731/problem/F 题意:有n个数,从里面选出来一个作为第一个,然后剩下的数要满足是这个数的倍数,如果不是,只能减小为他的 ...
- Codeforces 731F Video Cards
题意:给定n个数字,你可以从中选出一个数A(不能对该数进行修改操作),并对其它数减小至该数的倍数,统计总和.问总和最大是多少? 题解:排序后枚举每个数作为选出的数A,再枚举其他数, sum += a[ ...
- Codeforces Round #376 (Div. 2) F. Video Cards 数学 & 暴力
http://codeforces.com/contest/731/problem/F 注意到一个事实,如果你要找一段区间中(从小到大的),有多少个数是能整除左端点L的,就是[L, R]这样.那么,很 ...
- Codeforces731F Video Cards
考虑每个数在最大值内的倍数都求出来大概只有max(ai)ln(max(ai))个. 先排个序,然后对于每个数ai,考虑哪些数字可以变成ai*k. 显然就是区间[ai*k,ai*(k+1))内的数,这个 ...
- CodeForces 731F Video Cards (数论+暴力)
题意:给定 n 个数,可以对所有的数进行缩小,问你找出和最大的数,使得这些数都能整除这些数中最小的那个数. 析:用前缀和来做,先统计前 i 个数中有有多少数,然后再进行暴力去找最大值,每次都遍历这一段 ...
随机推荐
- Java 反射 Method的invoke回调调用任意方法
Java 反射 Method的invoke回调调用任意方法 @author ixenos 关键子:Method.Field.invoke方法指针/函数指针.回调函数 invoke回调流程示例 0.由C ...
- shell脚本学习(五)
1.统计文件的行数.单词数.字符数 1)行数: wc -l file cat file | wc -l 2)单词数 wc -w file cat file | wc -w 3)统计字符数 wc -c ...
- linux下IPC通信
# 管道( pipe ):管道是一种半双工的通信方式,数据只能单向流动,而且只能在具有亲缘关系的进程间使用.进程的亲缘关系通常是指父子进程关系. # 有名管道 (named pipe) : 有名管道也 ...
- LeetCode OJ 88. Merge Sorted Array
Given two sorted integer arrays nums1 and nums2, merge nums2 into nums1 as one sorted array. Note:Yo ...
- Multidimensional Arrays
Overview An array having more than two dimensions is called a multidimensional array in the MATLAB® ...
- 记2016商大ACM省赛
比赛前三天才得到省赛的非正式参赛名额,总有点哭笑不得,笑的是是我的终究是我的,跑不掉…… 哭的是现在就剩三天了,虽然最近也一直在参加训练赛,但一直是断断续续的,对自己现在的水平并没有太大的信心…… 虽 ...
- Gentoo安装详解(一) -- 安装基本系统
前期准备 远程登录: 开启ssh服务: /etc/init.d/sshd start 设置密码: passwd 以便使用putty.ssh client远程登录上传stage等(有时在线下载很慢,而局 ...
- 利用pscp命令实现linux与windows文件互传
windows==>linux(单个文件) PrivateKey.ppk(私钥)可以是相对路径或者绝对路径pscp -i D:\PrivateKey.ppk D:\xxx.xx root@123 ...
- 转载-ACPI的知识
ACPI – the Advanced Configuration & Power Interface. ACPI是OS,BIOS和硬件之间的抽象层.它允许OS和平台独立的发展,比如新的OS可 ...
- .Net_把文件数据添加到数据库中(面试题)
一个文本文件含有如下内容: 4580616022644994|3000|赵涛 4580616022645017|6000|张屹 4580616022645090|3200|郑欣夏 上述文件每行为一个转 ...