Question

嘿，我有一个课堂练习，我坚持，并希望得到任何帮助。程序应该随机选择1-5之间的数字并循环直到所有数字都被选中。然后它应该重复大约100次，以给出获得所有五个数字所需的平均数。我知道如何使用random.int，只是不知道如何编写一个循环，当所有5个数字被选中时它会中断。任何形式的帮助都会很棒。谢谢

Answer 1

我建议您使用Set。每次达到1-5之间的值时，将其放入您的集合中，然后当集合的大小为5时，打破循环。

Answer 2

这样做：

from random import randint
a = []
for _ in range(100):
    b = 0
    c = set()
    while len(c) < 5:
        c.add(randint(1, 5))
        b += 1
    a.append(b)
d = round(sum(a)/len(a))
print("{}\nAverage loops: {}".format(c, d))

记录版本：

# Import the `randint` function from `random`.
from random import randint
# This will hold the results that will later be used to calculate the average.
a = []
# This loops 100 times (to get data for a calculation of the average).
for _ in range(100):
    # This will be the number of times the while-loop loops.
    b = 0
    # This is a set to hold the choices of `random.randint`.
    # When it reaches 5 items, all numbers from 1-5 have been found.
    c = set()
    # Loop while the length of the set is less than 5.
    while len(c) < 5:
        # Add a new random number to the set,
        # If the number is already there, nothing happens.
        c.add(randint(1, 5))
        # Record a completed iteration of the while-loop.
        b += 1
    # Add the number of while-loop loops to `a`.
    a.append(b)
# The average is calculated by dividing the sum of `a` by the length of `a`.
# It is then rounded to the nearest integer.
d = round(sum(a)/len(a))
# Print the results.
print("{}\nAverage loops: {}".format(c, d))

示例输出：

{1, 2, 3, 4, 5}
Average loops: 12

{1, 2, 3, 4, 5}
Average loops: 10

{1, 2, 3, 4, 5}
Average loops: 9

Answer 3

我只是做一个while循环，它产生1-5之间的随机数，直到它得到第一个数字，t，记录它所花费的尝试次数。记录它所花费的尝试次数。下一个数字，当你完成时，找到它花了多少次尝试的平均值。

示例：

total = 0
for i in range(100):
    for n in range(1,6):
        generatedNum = 0
        while generatedNum != n:
            #generate random number
            total += 1
print (total/100)

Answer 4

这是我们可能使用的另一种方式：

import random

total = {1:0,2:0,3:0,4:0,5:0}

for k in xrange(100):                          #outter loop
    trial = {}
    n = 0                                      #counter
    while n<5:
        sample = random.randint(1,5)           #sample
        try:
            trial[sample] += 1
        except:
            n += 1
            trial[sample] = 1
    for i in xrange(1,6):                      #accumulate the results
        total[i] += trial[i]

会导致：

>>> total
{1: 221, 2: 255, 3: 246, 4: 213, 5: 243}

Python随机数循环

4 个答案: