Question

这是一个家庭作业问题。我正在定义一个函数，它接受一个单词并用另一个char替换给定的char。例如，替换（“蛋糕”，“a”，“o”）应该返回“我尝试过的可乐”

def replace(word,char1,char2):
    newString = ""
    for char1 in word:
        char1 = char2
        newString+=char1
    return newString  #returns 'oooo'

和

def replace(word,char1,char2):
    newString = ""
    if word[char1]:
        char1 = char2
        newString+=char1
    return newString  #TypeError: string indices must be integers, not str

我假设我的第一次尝试更接近我想要的。我的职能出了什么问题？

Answer 1

试试这个：

def replace(word,char1,char2):
    newString = ""
    for next_char in word:         # for each character in the word
        if next_char == char1:     # if it is the character you want to replace
            newString += char2     # add the new character to the new string
        else:                      # otherwise
            newString += next_char # add the original character to the new string
    return newString

尽管python中的字符串已经有了这样做的方法：

print "cake".replace("a", "o")

Answer 2

def replace(word, ch1, ch2) :
    return ''.join([ch2 if i == ch1 else i for i in word])

更换没有任何进口或内置功能？

2 个答案: