在python中求和两个或多个数字

I think you should explain once more.

you have the example "abc"

after replacing "a" with "2" you would have

"2bc"

What do you mean with adding 30 to "2bc" ?????

Please explain also what result you'd like to have for the string

"aabc" and what for "ababbc" ?

I suggest you explain step by step in your question what you'd like to have. Then it will be easy to write a program for it, but without some examples everybody will probably interpret your question differently and all you get will be wild guesses.

In fact writing an unambiguous question is rather difficult, but necessary if you want good answers.

One issue is, that you have to convert a string into a number (an int) before being able to do any arithmetic operation.

if you have the string "2" (e.g. a = "2" ) and you want to perform operations (add for example a 30 ), then you have to convert it (e.g. rslt = int(a) + 30 )

Also if you have numbers and you want to concatenate them, then you have to convert them to strings first. so with a=12 and b=54 you had to do str(a) + str(b) to get "1254" .

Her another attempt for an answer, but I have the impression I completely misinterpreted your question

请提供示例输入和示例预期结果，并逐步说明。例如，您为所有a仅添加30个还是要为每个a添加30个敌人？您对不是a，b或c的字母做什么？ ，...

orgtxt = input("Enter text: ")
charA = "a"
charB= "b"
charC="c"
num_to_add = 30

result = ""
for i in orgtxt:
    if i == charA:
        result = result + str(num_to_add + 2)
    elif i == charB:
        result = result + str(num_to_add + 22)
    elif i == charC:
        result = result + str(num_to_add + 222)


print(result)

如果这是您想要的，则以下应该产生相同的结果，不同之处在于，任何非a，b，c的字母将与第二个代码一起保留，而与第一个代码一起删除：

orgtxt = orgtxt.replace(charA, str(num_to_add + 2))
orgtxt = orgtxt.replace(charB, str(num_to_add + 22))
orgtxt = orgtxt.replace(charC, str(num_to_add + 222))

print(orgtxt)

回答来源：stackoverflow