# 973. K Closest Points to Origin 最接近原点的 K 个点

@TOC

## # 题目描述

We have a list of `points` on the plane. Find the `K` closest points to the origin `(0, 0)`.

(Here, the distance between two points on a plane is the Euclidean distance.)

You may return the answer in any order. The answer is guaranteed to be unique (except for the order that it is in.)

Example 1:

``````Input: points = [[1,3],[-2,2]], K = 1
Output: [[-2,2]]
Explanation:
The distance between (1, 3) and the origin is sqrt(10).
The distance between (-2, 2) and the origin is sqrt(8).
Since sqrt(8) < sqrt(10), (-2, 2) is closer to the origin.
We only want the closest K = 1 points from the origin, so the answer is just [[-2,2]].
``````

Example 2:

``````Input: points = [[3,3],[5,-1],[-2,4]], K = 2
Output: [[3,3],[-2,4]]
(The answer [[-2,4],[3,3]] would also be accepted.)
``````

Note:

1. `1 <= K <= points.length <= 10000`
2. `-10000 < points[i][0] < 10000`
3. `-10000 < points[i][1] < 10000`

## # 解题方法

### # 小根堆

python代码如下：

``````class Solution(object):
def kClosest(self, points, K):
"""
:type points: List[List[int]]
:type K: int
:rtype: List[List[int]]
"""
dis = []
for p in points:
d = math.sqrt(p[0] ** 2 + p[1] ** 2)
dis.append((d, p))
heapq.heapify(dis)
return [d[1] for d in heapq.nsmallest(K, dis)]
``````

## # 日期

2019 年 1 月 13 日 —— 时间太快了