UVa 10041 Vito's Family

Background

The world-known gangster Vito Deadstone is moving to New York. He has a very big family there, all of them living in Lamafia Avenue. Since he will visit all his relatives very often, he is trying to find a house close to them.

Problem

Vito wants to minimize the total distance to all of them and has blackmailed you to write a program that solves his problem.

Input

The input consists of several test cases. The first line contains the number of test cases.
For each test case you will be given the integer number of relatives r ( 0 < r < 500) and the street numbers (also integers) where they live ( 0 < si < 30000 ). Note that several relatives could live in the same street number.

Output

For each test case your program must write the minimal sum of distances from the optimal Vito’s house to each one of his relatives. The distance between two street numbers si and sj is dij= |si-sj|.

Sample Input

2
2 2 4
3 2 4 6

Sample Output

2
4

有一个人住在纽约，现在他有r个亲戚，这个人经常会去所有的亲戚家，现在他想找到一个房子，使得每一次他去访问所有的亲戚时候走的路是最短的，输出这个最小值。

想了半天以为很麻烦，结果就是一个求中位数的题。
C语言代码如下：

#include<stdio.h>
#include<math.h>
int main()
{
	int n,a[505],t,j,temp;
	int sum;
	scanf("%d",&n);
	while(n--)
	{
		int i=0;
		scanf("%d",&t);
		for(i=0;i<t;i++)
		{
			scanf(" %d",&a[i]);
		}
		for(i=0;i<t;i++)
			for(j=0;j<t-i-1;j++)
				if(a[j]>a[j+1])
				{
					temp=a[j];
					a[j]=a[j+1];
					a[j+1]=temp;
				}
		sum=0;
		temp=a[t/2];
			for(i=0;i<t;i++)
				sum+=abs(a[i]-temp);
		printf("%d
",sum);
	}
	return 0;
}