447. Number of Boomerangs

447. Number of Boomerangs

难度: Easy

刷题内容

原题连接

内容描述

Given n points in the plane that are all pairwise distinct, a "boomerang" is a tuple of points (i, j, k) such that the distance between i and j equals the distance between i and k (the order of the tuple matters).

Find the number of boomerangs. You may assume that n will be at most 500 and coordinates of points are all in the range [-10000, 10000] (inclusive).

Example:

Input:
[[0,0],[1,0],[2,0]]

Output:
2

Explanation:
The two boomerangs are [[1,0],[0,0],[2,0]] and [[1,0],[2,0],[0,0]]

思路 1
- 时间复杂度: O(N^3)- 空间复杂度: O(1)

首先我们需要注意的是这里的distance我们不要求根号,因为可能会有精度问题,直接用距离的平方就可以了

最暴力肯定就是O(N^3)了,但是超时

```python
class Solution:
def numberOfBoomerangs(self, points: List[List[int]]) -> int:
def getDistance(p1, p2):

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