# Tutor

Time Limit: 20 Sec  Memory Limit: 256 MB

## 题目连接

http://acm.hdu.edu.cn/showproblem.php?pid=4493

## Description

Lilin was a student of Tonghua Normal University. She is studying at University of Chicago now. Besides studying, she worked as a tutor teaching Chinese to Americans. So, she can earn some money per month. At the end of the year, Lilin wants to know his average monthly money to decide whether continue or not. But she is not good at calculation, so she ask for your help. Please write a program to help Lilin to calculate the average money her earned per month.

Input

The first line contain one integer T, means the total number of cases.
Every case will be twelve lines. Each line will contain the
money she earned per month. Each number will be positive and displayed
to the penny. No dollar sign will be included.

Output

The output will be a single number, the average of money she earned for the twelve months. It will be rounded to the nearest penny, preceded immediately by a dollar sign without tail zero. There will be no other spaces or characters in the output.

Sample Input

2
100.00
489.12
12454.12
1234.10
823.05
109.20
5.27
1542.25
839.18
83.99
1295.01
1.75
100.00
100.00
100.00
100.00
100.00
100.00
100.00
100.00
100.00
100.00
100.00
100.00

￥1581.42

￥100

## HINT

+0.005，这是一个特别屌的方法

```//qscqesze
#include <cstdio>
#include <cmath>
#include <cstring>
#include <ctime>
#include <iostream>
#include <algorithm>
#include <set>
#include <vector>
#include <sstream>
#include <queue>
#include <typeinfo>
#include <fstream>
#include <map>
#include <stack>
typedef long long ll;
using namespace std;
//freopen("D.in","r",stdin);
//freopen("D.out","w",stdout);
#define sspeed ios_base::sync_with_stdio(0);cin.tie(0)
#define test freopen("test.txt","r",stdin)
#define maxn 200001
#define mod 10007
#define eps 1e-9
int Num;
char CH[20];
const int inf=0x3f3f3f3f;
const ll infll = 0x3f3f3f3f3f3f3f3fLL;
{
ll x=0,f=1;char ch=getchar();
while(ch<‘0‘||ch>‘9‘){if(ch==‘-‘)f=-1;ch=getchar();}
while(ch>=‘0‘&&ch<=‘9‘){x=x*10+ch-‘0‘;ch=getchar();}
return x*f;
}
inline void P(int x)
{
Num=0;if(!x){putchar(‘0‘);puts("");return;}
while(x>0)CH[++Num]=x%10,x/=10;
while(Num)putchar(CH[Num--]+48);
puts("");
}
//**************************************************************************************

int dp[30][30][30][30];

int a[maxn];
int b[maxn];
int temp;
int solve(int l1,int r1,int l2,int r2)
{
if(dp[l1][r1][l2][r2]!=-1)
return dp[l1][r1][l2][r2];
if(l1>r1||l2>r2)
dp[l1][r1][l2][r2]=0;
int sum=0;
int ans=0;
if(l1<=r1)
sum+=a[r1]-a[l1-1];
if(l2<=r2)
sum+=b[r2]-b[l2-1];
if(l1<=r1)
{
ans=max(ans,sum-solve(l1+1,r1,l2,r2));
ans=max(ans,sum-solve(l1,r1-1,l2,r2));
}
if(l2<=r2)
{
ans=max(ans,sum-solve(l1,r1,l2+1,r2));
ans=max(ans,sum-solve(l1,r1,l2,r2-1));
}
return dp[l1][r1][l2][r2]=ans;
}
int main()
{
//test;
while(t--)
{
memset(dp,-1,sizeof(dp));
memset(a,0,sizeof(a));
memset(b,0,sizeof(b));
for(int i=1;i<=n;i++)
{
a[i]+=a[i-1]+temp;
}
for(int i=1;i<=n;i++)
{
b[i]+=b[i-1]+temp;
}
cout<<solve(1,n,1,n)<<endl;
}
}```

## hdu 4493 Tutor(简单处理题)

http://acm.hdu.edu.cn/showproblem.php?pid=4493 题意是输入12个数据,让你求平均值,但是要去除尾零,就像100.00只要输出100 其实这题有点不严密,像这组数据 2 100.995 100.995 100.995 100.995 100.995 100.995 100.995 100.995 100.995 100.995 100.995 100.995 输出100,其他可以过的输出100.10以及101都可以 用自己的方法死活不可以过,上网搜了一

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## hdu 5210 delete 水题

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## hdu 4802 GPA 水题

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