如何在python中多次添加相同的變量？

Question

這是我的代碼（Python 3.2）

Total = eval(input("How many numbers do you want to enter? "))
#say the user enters 3
for i in range(Total):
    Numbers = input("Please enter a number ")
#User enters in 1
#User enters in 2
#User enters in 3
print ("The sum of the numbers you entered is", Numbers)
#It displays 3 instead of 6

我如何正確加總？

Answer 1

只是對行的快速而骯臟的重寫：

Total = int(input("How many numbers do you want to enter? "))
#say the user enters 3
Numbers=[]
for i in range(Total):
    Numbers.append(int(input("Please enter a number "))
#User enters in 1
#User enters in 2
#User enters in 3
print ("The sum of the numbers you entered is", sum(Numbers))
#It displays 3 instead of 6

我假設您使用Python 3的原因在於print ，但是如果使用Python 2，請使用raw_input而不是input 。

Answer 2

此代碼將解決您的問題：

total = int(input("How many numbers do you want to enter? "))
#say the user enters 3
sum_input = 0
for i in range(total):
    sum_input += int(input("Please enter a number "))
#User enters in 1
#User enters in 2
#User enters in 3
print ("The sum of the numbers you entered are", sum_input)

---

一些評論：

1. 您應該堅持使用pep8作為樣式和變量名稱。 具體而言，使用under_store為變量名和功能名，和CapWords對類名。
2. 在這里使用eval值得懷疑。 本文很好地解釋了在大多數情況下為什么不應該使用eval的原因 。

Answer 3

您需要在for循環外聲明變量，並繼續在循環中向其添加輸入數字。

numbers = 0
for i in range(Total):
    numbers += int(input("Please enter a number "))

print ("The sum of the numbers you entered are", numbers)