[FIXED] What is wrong with python syntax?

Issue

im just getting into python for my discrete structures and algorithms class > and for some reason, im getting an error with my syntax and I don't understand why can you assist this is the error:

line 10

i = i + 1

IndentationError: unindent does not match any outer indentation level also for some reason my code isn't printing

#linear search algorithm
 def search(list1, n):
    i = 0

    while i < len(list1):
         if list1[i] == n:
            print("found now")
            return True
        i = i + 1

    return False


list1 = [1,5,9,3,4,6]
n = 6

if search(list1, n):
    print("found")
else:
    print("not found")

Solution

As others have mentioned in your comments, your indentation is wonky. Pythonic code prefers 4 spaces for every indented/unindented line.

To linear search for an element in a list data structure, you can use the in keyword. Here is your code functionally, but with less lines:

list1 = [1,5,9,3,4,6]
n = 6

if n in list1:
    print("found") # Indent 4 spaces
else: # Unindent 4 spaces
    print("not found") # Indent 4 spaces

Now for your code:

 def search(list1, n): # Careful! You have an extra space here.
    i = 0 # Indent 3 spaces

    while i < len(list1):
         if list1[i] == n: # Indent 5 spaces
            print("found now") # Indent 3 spaces
            return True
        i = i + 1 # Unindent 4 spaces

    return False # Unindent 4 spaces

So remove the extra space at the start, and fix it to 4 spaces each time.

Note: The in keyword can be used on other iterables (tuples, dictionaries, sets, etc...) as well, or objects with __contains__ in the class.

Since this is a class, they probably just want you to familiarize yourself with linear search by using an index variable (e.g. for i in ....) as you've done, but the python already does this for you in the background with the in keyword.

Answered By - jsonV