Python - 替换给定单词以外的所有单词

给定一个字符串。任务是用“？”替换所有单词。除了给定的单词 K。

例子：

Input : test_str = ‘gfg is best for geeks’, K = “gfg”, repl_char = “?” 
Output : gfg ? ? ? ? 
Explanation : All words except gfg is replaced by ?.

Input : test_str = ‘gfg is best for gfg’, K = “gfg”, repl_char = “?” 
Output : gfg ? ? ? gfg 
Explanation : All words except gfg is replaced by ?. 

方法 #1：使用 split() + join() + 循环

这是可以执行此任务的粗暴方式。在此，我们使用 split() 执行将字符串更改为单词列表的任务，然后检查 K 个单词，如果未找到，则将其替换为适当的值。最后，使用 join() 转换回字符串。

Python3

# Python3 code to demonstrate working of
# Replace all words not K
# Using join() + split() + loop
  
# initializing string
test_str = 'gfg is best for geeks gfg is for cs I love gfg'
  
# printing original string
print("The original string is : " + str(test_str))
  
# initializing K
K = "gfg"
  
# initializing repl_char
repl_char = "?"
  
# extracting words
temp = test_str.split(" ")
for idx in range(len(temp)):
    ele = temp[idx]
  
    # replace non K with repl_char
    if not ele == K:
        temp[idx] = repl_char
  
# joining result
res = " ".join(temp)
  
# printing result
print("The resultant string : " + str(res))

输出：

The original string is : gfg is best for geeks gfg is for cs I love gfg
The resultant string : gfg ? ? ? ? gfg ? ? ? ? ? gfg

方法#2：使用列表理解 

这是可以执行此任务的另一种方式。在这种情况下，我们迭代元素并使用与上述方法类似的功能使用 one-liner 执行任务。

蟒蛇3

# Python3 code to demonstrate working of
# Replace all words not K
# Using list comprehension
  
# initializing string
test_str = 'gfg is best for geeks gfg is for cs I love gfg'
  
# printing original string
print("The original string is : " + str(test_str))
  
# initializing K
K = "gfg"
  
# initializing repl_char
repl_char = "?"
  
# using one-liner to solve this problem
res = " ".join(
    [repl_char if not ele == K else ele for ele in test_str.split()])
  
# printing result
print("The resultant string : " + str(res))

输出：

The original string is : gfg is best for geeks gfg is for cs I love gfg
The resultant string : gfg ? ? ? ? gfg ? ? ? ? ? gfg