LIGHTOJ-1043 -Triangle Partitioning

快来打我* 2022-08-18 02:38 159阅读 0赞

1043 - Triangle Partitioning

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   <td style="color:rgb(121,114,104); background:rgb(245,250,250)">Time Limit:&nbsp;<span style="color:rgb(180,95,4)">0.5 second(s)</span></td> 
   <td style="color:rgb(121,114,104); background:rgb(245,250,250)">Memory Limit:&nbsp;<span style="color:rgb(180,95,4)">32 MB</span></td> 
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See the picture below.

![a.png][]

You are given **AB**, **AC** and **BC**. **DE** is parallel to **BC**. You are also given the area ratio between **ADE** and **BDEC**. You have to find the value of **AD**.

# Input #

Input starts with an integer **T (≤ 25)**, denoting the number of test cases.

Each case begins with four real numbers denoting **AB, AC, BC** and the ratio of **ADE** and **BDEC (ADE / BDEC)**. You can safely assume that the given triangle is a valid triangle with positive area.

# Output #

For each case of input you have to print the case number and **AD**. Errors less than **10\-6** will be ignored.

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   <td> <h1 style="color:green">Sample Input</h1> </td> 
   <td> <h1 style="color:green">Output for Sample Input</h1> </td> 
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   <td> <p>4</p> <p>100 100 100 2</p> <p>10 12 14 1</p> <p>7 8 9 10</p> <p>8.134 9.098 7.123 5.10</p> </td> 
   <td> <p>Case 1: 81.6496580</p> <p>Case 2: 7.07106781</p> <p>Case 3: 6.6742381247</p> <p>Case 4: 7.437454786</p> </td> 
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数学题，用相似三角形解出AD长度解出公式即可

#include<cstdio>
    #include<cstring>
    #include<cmath>
    #include<algorithm>
    using namespace std;
    int main()
    {
    	int m,n,i,j,cot=1;
    	double a,b,c,d,r;
    	scanf("%d",&m);
    	while(m--)
    	{
    		scanf("%lf%lf%lf%lf",&a,&b,&c,&d);
    		r=sqrt(d/(d+1))*a;
    		printf("Case %d: %.7lf\n",cot++,r);
    	}
    	return 0;
     }

[a.png]: /images/20220731/d047cdbecfba46f79cdeceac695a9b10.png