求解任意两个点的距离的问题，用C语言程序的设计的方式来做怎么做呢

Question

Problem Description
PM Room defines a sequence A = {A1, A2,..., AN}, each of which is either 0 or 1. In order to beat him, programmer Moor has to construct another sequence B = {B1, B2,... , BN} of the same length, which satisfies that:

Input
The input consists of multiple test cases. The number of test cases T(T<=100) occurs in the first line of input.

For each test case:
The first line contains a single integer N (1<=N<=100000), which denotes the length of A and B.
The second line consists of N integers, where the ith denotes Ai.

Output
Output the minimal f (A, B) when B is optimal and round it to 6 decimals.

Sample Input
4
9
1 1 1 1 1 0 0 1 1
9
1 1 0 0 1 1 1 1 1
4
0 0 1 1
4
0 1 1 1

Sample Output
1.428571
1.000000
0.000000
0.000000

Answer 1

1、获取两个点坐标。
2、可以用正弦定理求两个坐标点X轴距离跟Y轴距离形成的斜线：length = sqrt(x*x+y*y)