Python String find() method
Python String find() method returns the lowest index of the substring if it is found in a given string. If it is not found then it returns -1.
Syntax:
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str.find(sub, start, end)
Parameters:
- sub: It’s the substring that needs to be searched in the given string.
- start: Starting position where the sub needs to be checked within the string.
- end: Ending position where suffix needs to be checked within the string.
Note #1: If start and end indexes are not provided then by default it takes 0 and length-1 as starting and ending indexes where ending indexes are not included in our search.
Returns:
Returns the lowest index of the substring if it is found in a given string. If it’s not found then it returns -1.
Note #2: The find() method is similar to index(). The only difference is find() returns -1 if the searched string is not found and index() throws an exception in this case.
Example 1: find() With No start and end Argument
Python3
word = 'geeks for geeks' # returns first occurrence of Substring result = word.find('geeks') print ("Substring 'geeks' found at index:", result ) result = word.find('for') print ("Substring 'for ' found at index:", result ) # How to use find() if (word.find('pawan') != -1): print ("Contains given substring ") else: print ("Doesn't contains given substring") |
Output:
Substring 'geeks' found at index: 0 Substring 'for ' found at index: 6 Doesn't contains given substring
Example 2: find() With start and end Arguments
Python3
word = 'geeks for geeks' # Substring is searched in 'eks for geeks' print(word.find('ge', 2)) # Substring is searched in 'eks for geeks' print(word.find('geeks ', 2)) # Substring is searched in 's for g' print(word.find('g', 4, 10)) # Substring is searched in 's for g' print(word.find('for ', 4, 11)) |
Output:
10 -1 -1 6
