Question

我想打印出结果1：正面，结果2：背面等，但我只能一直打印到结果1。我如何积累它？

import random

heads = 0
tails = 0
toss = heads + tails

count = int(input("How many coin tosses would you like to simulate?"))
max_result,curr_result = 0,0
max_head_streak,max_tail_streak,curr_head_streak,curr_tail_streak = 0,0,0,0

while heads + tails < count:
    coin = random.randint(1, 2)
    if coin == 1:
        heads = heads + 1
        curr_head_streak += 1
        curr_tail_streak = 0
        print("Result",curr_result + 1,": Heads")
    else:
        tails = tails + 1
        curr_tail_streak += 1
        curr_head_streak = 0
        print("Result",curr_result + 1,": Tails")
        
    max_head_streak = max(max_head_streak,curr_head_streak)
    max_tail_streak = max(max_tail_streak,curr_tail_streak)
    
print("The total amount of heads: ",heads)
print("the best streak of heads: ",max_head_streak)
print("The total amount of tails: ",tails)
print("The best streak of tails: ",max_tail_streak)

该程序的其余部分按我想要的方式工作。

Answer 1

您不会更新curr_result变量

建议的解决方案：

import random

heads = 0
tails = 0
toss = heads + tails

count = int(input("How many coin tosses would you like to simulate?"))
max_result,curr_result = 0,0
max_head_streak,max_tail_streak,curr_head_streak,curr_tail_streak = 0,0,0,0

while heads + tails < count:
    coin = random.randint(1, 2)
    curr_result += 1
    if coin == 1:
        heads = heads + 1
        curr_head_streak += 1
        curr_tail_streak = 0
        print("Result",curr_result,": Heads")
    else:
        tails = tails + 1
        curr_tail_streak += 1
        curr_head_streak = 0
        print("Result",curr_result,": Tails")
        
    max_head_streak = max(max_head_streak,curr_head_streak)
    max_tail_streak = max(max_tail_streak,curr_tail_streak)
    
print("The total amount of heads: ",heads)
print("the best streak of heads: ",max_head_streak)
print("The total amount of tails: ",tails)
print("The best streak of tails: ",max_tail_streak)

Answer 2

在第8行的while循环上方，将变量curr_result初始化为等于0。

然后在您编写的第17和22行中引用此变量：

print("Result",curr_result + 1,": Heads")

print("Result",curr_result + 1,": Tails")

由于您已将curr_result初始化为等于0，因此在第一次迭代中，将打印其中任何一个

Result1: Heads

或

Result1: Tails

但是，当程序再次迭代时，curr_result仍等于0，因为您实际上尚未更新变量，所以您只打印了变量加一。

为解决此问题，我建议在if / else语句下添加以下行，但仍在while循环内：

curr_result += 1

Answer 3

其他人似乎已经回答了为什么您的代码无法正常工作，因此这只是使用itertools.groupby和collections.defaultdict解决问题的另一种方法：

import random
from collections import defaultdict
from itertools import groupby

count = int(input("How many coin tosses would you like to simulate? "))

tally = defaultdict(int)
results = []
sides = ["tails", "heads"]
for i in range(count):
    side = random.choice(sides)
    tally[side] += 1
    results.append(side)

# Iterates over results, creating groups by repeated entries.
groups = [list(g) for _, g in groupby(results)]

# filters the given list of groups for the different results,
# and gives it to the max function
heads_streak = max([len(l) for l in groups if "heads" in l])
tails_streak = max([len(l) for l in groups if "tails" in l])

print(f"The total amount of heads: {tally['heads']}")
print(f"the best streak of heads: {heads_streak}")
print(f"The total amount of tails: {tally['tails']}")
print(f"the best streak of tails: {tails_streak}")
print(results)

输出：

How many coin tosses would you like to simulate? 10
The total amount of heads: 5
the best streak of heads: 2
The total amount of tails: 5
the best streak of tails: 2
['tails', 'heads', 'heads', 'tails', 'heads', 'tails', 'tails', 'heads', 'tails', 'heads']

编辑：上面的代码在groups中始终存在两种类型的值的前提下工作。我们可以使用"walrus operator" (new in 3.8)来更改该行为：

heads_streak = max(x if (x := [len(l) for l in groups if "heads" in l]) else [0])
tails_streak = max(x if (x := [len(l) for l in groups if "tails" in l]) else [0])

不是我编写的最漂亮的代码，但是它似乎可以工作。

Answer 4

您不增加curr_result的值。也许您想使用for循环？这可以实现与while循环相同的作用：

import random

heads = 0
tails = 0
toss = heads + tails

count = int(input("How many coin tosses would you like to simulate?"))
max_result = 0
max_head_streak,max_tail_streak,curr_head_streak,curr_tail_streak = 0,0,0,0

for curr_result in range(count):
    coin = random.randint(1, 2)
    if coin == 1:
        heads = heads + 1
        curr_head_streak += 1
        curr_tail_streak = 0
        print("Result", curr_result + 1,": Heads")
    else:
        tails = tails + 1
        curr_tail_streak += 1
        curr_head_streak = 0
        print("Result", curr_result + 1,": Tails")

    max_head_streak = max(max_head_streak,curr_head_streak)
    max_tail_streak = max(max_tail_streak,curr_tail_streak)

print("The total amount of heads: ",heads)
print("the best streak of heads: ",max_head_streak)
print("The total amount of tails: ",tails)
print("The best streak of tails: ",max_tail_streak)

我无法累积结果数

4 个答案: