Python中的回旋镖数量
因此，如果输入像[[0,0]，[1,0]，[2,0]]，则输出将为2，因为两个回旋镖分别为[[1,0]，[0,0]，[[2,0]]和[[1,0]，[2,0]，[0,0]]。
为了解决这个问题，我们将遵循以下步骤-
counter_of_boomerangs：=0
对于点数组中的每个point_1，执行
n：=distance_count_dict[d]
counter_of_boomerangs：=counter_of_boomerangs+n*(n-1)
x2，y2=point_2
diff_x：=x2-x1
diff_y：=y2-y1
dist：=diff_x^2+diff_y^2
distance_count_dict[dist]：=distance_count_dict[dist]+1
x1，y1=point_1
定义一个名为distance_count_dict的映射
对于点数组中的每个point_2，执行
对于distance_count_dict中的每个d-
返回counter_of_boomerangs
例
让我们看下面的实现以更好地理解-
from collections import defaultdict
class Solution:
def numberOfBoomerangs(self, points):
counter_of_boomerangs = 0
for point_1 in points:
x1, y1 = point_1
distance_count_dict = defaultdict( int )
for point_2 in points:
x2, y2 = point_2
diff_x = x2-x1
diff_y = y2-y1
dist = diff_x ** 2 + diff_y ** 2
distance_count_dict[ dist ] += 1
for d in distance_count_dict:
n = distance_count_dict[d]
counter_of_boomerangs += n * (n-1)
return counter_of_boomerangs
ob = Solution()print(ob.numberOfBoomerangs([[0,0],[1,0],[2,0]]))输入值
[[0,0],[1,0],[2,0]]
输出结果
0