Itertools.product() (Python 3)

• URL : https://www.hackerrank.com/challenges/itertools-product/problem
• This tool computes the cartesian product of input iterables.
• It is equivalent to nested for-loops.

• For example, product(A, B) returns the same as ((x,y) for x in A for y in B).

• Sample Code

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  >>> from itertools import product >>> >>> print list(product([1,2,3],repeat = 2)) [(1, 1), (1, 2), (1, 3), (2, 1), (2, 2), (2, 3), (3, 1), (3, 2), (3, 3)] >>> >>> print list(product([1,2,3],[3,4])) [(1, 3), (1, 4), (2, 3), (2, 4), (3, 3), (3, 4)] >>> >>> A = [[1,2,3],[3,4,5]] >>> print list(product(*A)) [(1, 3), (1, 4), (1, 5), (2, 3), (2, 4), (2, 5), (3, 3), (3, 4), (3, 5)] >>> >>> B = [[1,2,3],[3,4,5],[7,8]] >>> print list(product(*B)) [(1, 3, 7), (1, 3, 8), (1, 4, 7), (1, 4, 8), (1, 5, 7), (1, 5, 8), (2, 3, 7), (2, 3, 8), (2, 4, 7), (2, 4, 8), (2, 5, 7), (2, 5, 8), (3, 3, 7), (3, 3, 8), (3, 4, 7), (3, 4, 8), (3, 5, 7), (3, 5, 8)]

• Task
  • You are given a two lists A and B. Your task is to compute their cartesian product A X B.
• Example ```python A = [1, 2] B = [3, 4]

AxB = [(1, 3), (1, 4), (2, 3), (2, 4)]

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- Note: A and B are sorted lists, and the cartesian product's tuples should be output in sorted order.

- Input Format
    - The first line contains the space separated elements of list A.
    - The second line contains the space separated elements of list B.
    - Both lists have no duplicate integer elements.

- Constraints
    - 0 < A < 30
    - 0 < B < 30

- Output Format
    - Output the space separated tuples of the cartesian product.

#### 문제풀이
- list A와 B가 주어졌을때 A X B 의 데카르트의 곱을 구하는 것
- python의 product를 사용하였고, list형태로 받은뒤 해당 list의 원소를 for문으로 print하는 형식으로 만듬
- 아마 다른방법도 있을듯 하다..


```python
from itertools import product
A = list(map(int,(input().split())))
B = list(map(int,(input().split())))
p = list(product(A,B))
for i in p:
    print(i, end=' ')

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(1, 3) (1, 4) (2, 3) (2, 4) 

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