CodeForces - 589B(暴力+排序)
Dasha decided to bake a big and tasty layer cake. In order to do that she went shopping and bought n rectangular cake layers. The length and the width of the i-th cake layer were ai and birespectively, while the height of each cake layer was equal to one.
From a cooking book Dasha learned that a cake must have a form of a rectangular parallelepiped constructed from cake layers of the same sizes.
Dasha decided to bake the biggest possible cake from the bought cake layers (possibly, using only some of them). It means that she wants the volume of the cake to be as big as possible. To reach this goal, Dasha can cut rectangular pieces out of the bought cake layers. She always cuts cake layers in such a way that cutting lines are parallel to the edges of that cake layer. Dasha isn't very good at geometry, so after cutting out a piece from the original cake layer, she throws away the remaining part of it. Also she can rotate a cake layer in the horizontal plane (swap its width and length).
Dasha wants her cake to be constructed as a stack of cake layers of the same sizes. Each layer of the resulting cake should be made out of only one cake layer (the original one or cut out from the original cake layer).
Help Dasha to calculate the maximum possible volume of the cake she can bake using given cake layers.
Input
The first line contains an integer n (1 ≤ n ≤ 4000) — the number of cake layers that Dasha can use.
Each of the following n lines contains two integer numbers ai and bi (1 ≤ ai, bi ≤ 106) — the length and the width of i-th cake layer respectively.
Output
The first line of the output should contain the maximum volume of cake that can be baked using given layers.
The second line of the output should contain the length and the width of the resulting cake. If there are many solutions with maximum possible volume, print any of them.
Examples
5
5 12
1 1
4 6
6 4
4 6
96
6 4
2
100001 900000
900001 100000
180000000000
900000 100000
Note
In the first example Dasha doesn't use the second cake layer. She cuts 4 × 6 rectangle from the first cake layer and she uses other cake layers as is.
In the second example Dasha cuts off slightly from the both cake layers.
题意:给出n层蛋糕,每一层的蛋糕的长和宽分别为为 l,和 w,高为 1 ,要你求出把这个蛋糕的每层的长和宽都切成一样的时候可以得到的最大的体积(每一层的蛋糕切完的时候多余的部分会舍去)(可以完全把一层蛋糕舍去) (可以把某一层的蛋糕旋转)。
思路:写这道题目的时候想了想怎么用贪心来切,没想到怎么去贪,后面看了题目给的时间,就想用暴力应该可以过,但是如果不作任何优化的话肯定会超时,后面想了想可不可以通过排序来
优化一下,但是一开始傻了一下,想当然的以为排序暴力的时间是n*n* n*log2 n,比n*n*n还要大,就否认了这种方法,但实际上降为了n*(n+n*log2 n),以后做题不能这样了啊,引以为戒。
代码:
#include<cstdio>
#include<algorithm>
#define ll long long
using namespace std;
struct st{
ll w,l;
}s[4040];
bool cmp(st a,st b){
return a.w<b.w;
}
ll wl[4040];
int main(){
ll n;
ll a,b;
ll i,j,k;
scanf("%lld",&n);
for(i=0;i<n;i++){
scanf("%lld%lld",&a,&b);
if(a>b){
s[i].l=a;
s[i].w=b;
}
else{
s[i].l=b;
s[i].w=a;
}
}
sort(s,s+n,cmp);
ll w,l;
ll w1,l1;
ll sum;
ll ans=0;
w=s[0].w-1;
for(i=0;i<n;i++){
if(w==s[i].w)
continue;
w=s[i].w;
for(k=0,j=i;j<n;j++,k++){//拿出宽度大于等于要切宽度的蛋糕层
wl[k]=s[j].l;
}
sort(wl,wl+k);//把他们的长从小到大排序
sum=0;
l=wl[0]-1;
for(j=0;j<k;j++){
if(l==wl[j])
continue;
l=wl[j];
sum=w*l*(k-j);//因为长度是递增的,所以枚举的长度中有k-j 层蛋糕满足条件
if(ans<sum){
ans=sum;
w1=w;
l1=l;
}
}
}
printf("%lld\n",ans);
printf("%lld %lld\n",l1,w1);
return 0;
}
CodeForces - 589B(暴力+排序)的更多相关文章
- CodeForces 589B Layer Cake (暴力)
题意:给定 n 个矩形是a*b的,问你把每一块都分成一样的,然后全放一块,高度都是1,体积最大是多少. 析:这个题,当时并没有完全读懂题意,而且也不怎么会做,没想到就是一个暴力,先排序,先从大的开始选 ...
- CodeForces - 589B(暴力)
题目链接:http://codeforces.com/problemset/problem/589/B 题目大意:告诉你n 个矩形,知道矩形的长度和宽度(长和宽可以互换),每个矩形的长度可以剪掉一部分 ...
- CodeForces 670D1 暴力或二分
今天,开博客,,,激动,第一次啊 嗯,,先来发水题纪念一下 D1. Magic Powder - 1 This problem is given in two versions that diff ...
- Codeforces Round #439 (Div. 2) Problem E (Codeforces 869E) - 暴力 - 随机化 - 二维树状数组 - 差分
Adieu l'ami. Koyomi is helping Oshino, an acquaintance of his, to take care of an open space around ...
- Codeforces Round #439 (Div. 2) Problem A (Codeforces 869A) - 暴力
Rock... Paper! After Karen have found the deterministic winning (losing?) strategy for rock-paper-sc ...
- Codeforces Round #425 (Div. 2) Problem B Petya and Exam (Codeforces 832B) - 暴力
It's hard times now. Today Petya needs to score 100 points on Informatics exam. The tasks seem easy ...
- Codeforces Round #424 (Div. 2, rated, based on VK Cup Finals) Problem C (Codeforces 831C) - 暴力 - 二分法
Polycarp watched TV-show where k jury members one by one rated a participant by adding him a certain ...
- codeforces 691F 暴力
传送门:https://codeforces.com/contest/691/problem/F 题意:给你n个数和q次询问,每次询问问你有多少对ai,aj满足ai*aj>=q[i],注意 a* ...
- CodeForces 558E(计数排序+线段树优化)
题意:一个长度为n的字符串(只包含26个小字母)有q次操作 对于每次操作 给一个区间 和k k为1把该区间的字符不降序排序 k为0把该区间的字符不升序排序 求q次操作后所得字符串 思路: 该题数据规模 ...
随机推荐
- 关于ajax返回数据处理
查看jquery文档,我们知道jquery有很多种Ajax调用方法,下面结合springmvc返回的数据,假设返回的是data ='{"label":"1",& ...
- C# 调用C++的dll 那些事
之前从来没搞过C++,最近被安排的任务需要调用C++的接口,对于一个没用过 Dependency 的小白来说,原本以为像平时的Http接口那样,协议,端口一定义,方法参数一写就没事,结果踩了无数的坑. ...
- python str find & index 联系
[1]相同点 (1)功能:检测字符串中是否包含子字符串str (2)语法: [1] str.find(str, beg = 0, end = len(string)) [2] str.index(st ...
- Numpy 数据类型和基本操作
Numpy 数据类型 bool 用一位存储的布尔类型(值为TRUE或FALSE) inti 由所在平台决定其精度的整数(一般为int32或int64) int8 整数,范围为128至127 int1 ...
- P3648 [APIO2014]序列分割(斜率优化dp)
P3648 [APIO2014]序列分割 我们先证明,分块的顺序对结果没有影响. 我们有一个长度为3的序列$abc$ 现在我们将$a,b,c$分开来 随意枚举一种分块方法,如$(ab)(c)$,$(a ...
- 02:openf-falcon安装
open-falcon其他篇 目录: 1.1 安装open-falcon环境准备 1.2 部署open-falcon后端 1.2.1 agent配置文件 1.2.2 transfer(数据上报) 1. ...
- git的一些补充点
git rm和 rm的区别 git rm是删除文件, 同时加入到git的跟踪管理中,做一个登记,那么在git commit的时候, 会把这次删除作为一次修改提交上去, 否则, 在 git log中你就 ...
- 在 Linux 上使用 VirtualBox 的命令行管理界面
VirtualBox 拥有一套命令行工具,你可以使用 VirtualBox 的命令行界面 (CLI) 对远程无界面的服务器上的虚拟机进行管理操作.在这篇教程中,你将会学到如何在没有 GUI 的情况下使 ...
- R语言-默认镜像设置
问题1:如何设置默认镜像 你希望下载某些R包,因此希望设定默认的CRAN网站镜像,这样R每次下载时不需要你选择镜像. 解决方案 该方案要求用户R系统中包含一个.Rprofile文件,如方法3.16描述 ...
- 《HTTP 权威指南》笔记:第十六章&第十七章 国际化、内容协商与转码
<HTTP 权威指南>笔记:第十六章 国际化 客户端通过在请求报文中的 Accept-Language 首部和 Accept-Charset 首部来告知服务器:“我理解这些语言.”服务器通 ...