2

我有一个任务来制作一个程序,我在其中得到 m、n 和 k。我应该创建一个带有n*m元素的列表。列表b应该有n*m元素。它是从列表 a 创建的,对于列表的 m 个元素,循环移位 k 到右侧。我知道这解释得不好。示例是:

n=3
m=4
A=1 2 3 4 5 6 7 8 9 10 11 12
k=1
B=4 1 2 3 8 5 6 7 12 9 10 11

我目前拥有的是:

from random import randint
n = int(input())
m=int(input())

A = []
B=[0]
B=B*n*m
for i in range(n*m):
    A = A + [randint(1, 30)]

print('\nLista A:\n')
for i in range(n*m):
    print(A[i], end = ' ')

print()

k=int(input())

for i in range(-1, m*n, m):
    B[m-1-i]=A[i]
    print(B[m-1-i])

print('\nLista B:\n')
for i in range(n*m):
    print(B[i], end = ' ')

谢谢

4

2 回答 2

1

尝试这个...

# Start with an empty list
B = []
# Take A in chunks of m
for i in range( int(len(A)/m) ):
    # Take an m-sized chunk of A
    chunk = A[m*i:m*(i+1)]
    # Shift it to the right by k (python style!)
    shift = chunk[-k:] + chunk[:-k]
    # Add it to B
    B += shift
print (B)
于 2016-10-17T14:38:32.443 回答
0

选择:

m=4
n=3
k=1

A=list(range(1,1+m*n))
print (A)

t_1=[A[_:_+4] for _ in range(0,len(A), 4)]
print (t_1)

t_2=[]
for sublist in t_1:
    t_2.append(sublist[-k:]+sublist[:-k])
print (t_2)

B=[]
for sublist in t_2:
    B.extend(sublist)

print (B)

如果您想要更快的速度,那么您可以使用集合模块中的双端队列来构建t_2

这是结果。

[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
[[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12]]
[[4, 1, 2, 3], [8, 5, 6, 7], [12, 9, 10, 11]]
[4, 1, 2, 3, 8, 5, 6, 7, 12, 9, 10, 11]
于 2016-10-17T14:56:58.567 回答