python - 找出所有可能的偶数或奇数组合并对结果进行数学运算

Question

我试图从三个列表中的每一个中取一个整数来找到所有可能的组合。组合必须包含所有偶数或所有奇数。

然后我想找到每个组合中整数的平方和。

最后，我想创建一个字典，使用这个值作为键，并使用它作为存储值的组合。

例如对于组合 (1,3,1)：键是整数 11（来自总和 (1^2) + (3^2) + (1^2)），存储的值是 (1, 3,1)

到目前为止我的代码：

lists = [[0,1,2,3,4,5,6],[0,1,2,3,4,5,6],[0,1,2,3,4,5,6]] 

combos = np.array([list(i) for i in np.array(np.meshgrid(*values)).T.reshape(-1,len(values))])

这需要三个列表，每个列表都包含整数 0-6

并使用每个列表中的一个元素来创建三个整数的组合

所有可能的组合结果：[0,0,0], [0,1,0], [0,2,0], [1,0,0] ... [6,6,6]

标签： pythondictionarycombinations

Answer 1

一种解决方案。

代码

from itertools import product

lsts = [[0,1,2,3,4,5,6],[0,1,2,3,4,5,6],[0,1,2,3,4,5,6]] 

# Product generates all combinations of taking one from each list
combos = product(*lsts)

# We filter for the combinations with all odd or even
# using generator i.e. () but could have been a list i.e. []
valid = (c for c in combos if all(x%2==0 for x in c) or all(x%2==1 for x in c))

# Dictionary key is sum of the squares of c
d = {sum(map(lambda i : i * i, c)) : c for c in valid}

# Pretty Print result
import pprint
pprint.pprint(d)

输出

{0: (0, 0, 0),
 3: (1, 1, 1),
 4: (2, 0, 0),
 8: (2, 2, 0),
 11: (3, 1, 1),
 12: (2, 2, 2),
 16: (4, 0, 0),
 19: (3, 3, 1),
 20: (4, 2, 0),
 24: (4, 2, 2),
 27: (5, 1, 1),
 32: (4, 4, 0),
 35: (5, 3, 1),
 36: (6, 0, 0),
 40: (6, 2, 0),
 43: (5, 3, 3),
 44: (6, 2, 2),
 48: (4, 4, 4),
 51: (5, 5, 1),
 52: (6, 4, 0),
 56: (6, 4, 2),
 59: (5, 5, 3),
 68: (6, 4, 4),
 72: (6, 6, 0),
 75: (5, 5, 5),
 76: (6, 6, 2),
 88: (6, 6, 4),
 108: (6, 6, 6)}