Teaching Kids Programming – Implement the String.Find Method in Python


Teaching Kids Programming: Videos on Data Structures and Algorithms

In Python, we can use the string.find method to search for a character: return the index of the first occurence if found or -1 if not found. This method applies to string only. We can implement such find method using the linear search.

1
2
3
4
5
6
7
def find(s, target):
  if type(s) != str:
    raise Exception("only works on str")
  for i, v in enumerate(s):
    if v == target:
      return i
  return -1 
def find(s, target):
  if type(s) != str:
    raise Exception("only works on str")
  for i, v in enumerate(s):
    if v == target:
      return i
  return -1 

We use the enumerate function to access the index and value in a tuple/pair. The time complexity of a linear search is O(N) time where N is the number of the chracters in the string. And the space complexity is O(1).

–EOF (The Ultimate Computing & Technology Blog) —

GD Star Rating
loading...
231 words
Last Post: C Macro/Function to Convert a IP Address into a 32-bit Integer
Next Post: Longest Distinct Sublist via Sliding Window (Two Pointer) Algorithm

The Permanent URL is: Teaching Kids Programming – Implement the String.Find Method in Python

Leave a Reply