Question: Modify the find function in the program below so that it has a third p

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Question: Modify the find function in the program below so that it has a third parameter, the index in the string where it should start looking.

def find(str, ch):
   index = 0
   while index < len(str):
      if str[index] == ch:
         return index
      index = index + 1
   return -1

In a sense, find is the opposite of the [] operator. Instead of taking an index and
extracting the corresponding character, it takes a character and finds the index
where that character appears. If the character is not found, the function returns
-1.
This is the first example we have seen of a return statement inside a loop. If
str[index] == ch, the function returns immediately, breaking out of the loop
prematurely.
If the character doesn’t appear in the string, then the program exits the loop
normally and returns -1.
This pattern of computation is sometimes called a “eureka” traversal because as
soon as we find what we are looking for, we can cry “Eureka!” and stop looking. Question: Modify the find function in the program below so that it has a third parameter, the index in the string where it should start looking.

def find(str, ch):
   index = 0
   while index < len(str):
      if str[index] == ch:
         return index
      index = index + 1
   return -1

In a sense, find is the opposite of the [] operator. Instead of taking an index and
extracting the corresponding character, it takes a character and finds the index
where that character appears. If the character is not found, the function returns
-1.
This is the first example we have seen of a return statement inside a loop. If
str[index] == ch, the function returns immediately, breaking out of the loop
prematurely.
If the character doesn’t appear in the string, then the program exits the loop
normally and returns -1.
This pattern of computation is sometimes called a “eureka” traversal because as
soon as we find what we are looking for, we can cry “Eureka!” and stop looking.

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