生成列表中的随机项目

Question

How do I adjust this function so if it is run multiple times it does not return the previous direction? For example, if it generated N , the next time it would not return N .

import random
def random_direct():
    directions=['N','S','E','W']
    return random.choice(directions)

Thanks for your time!

This question asks to return the random item not print it.

Answer 1

import random

def random_direct(prev_direction=None):
    directions = [direction for direction in ('N','S','E','W')
                            if direction != prev_direction]
    return random.choice(directions)

Answer 2

If you can pass previous direction as in another answer, it's the best. If you cannot, you can do some hackery (I do not recommend it):

def random_direct(_prev = [None]):
    directions = [direction for direction in ('N', 'S', 'E', 'W')
                            if direction != _prev[0]]
    res = random.choice(directions)
    _prev[0] = res
    return res

Call the function without any parameters, like random_direct() .