Insertion Sort in Python

Basic implementation of insertion sort algorithm

[rockingamingwiththesahit]

I'm trying my luck to be a good programmer in Python by watching this Playlist.See me in 7 years or so

[janicknorman]

holy sh&t, Khan is also a programmer?

[malteeaser]

def insertion_sort(A):
    for j in range(1, len(A)):
        key = A[j]
        i = j - 1
        while i >= 0 and A[i] > key:
            A[i + 1] = A[i]
            i = i - 1
        A[i+1] = key
    return A

[yusufdemir]

def insertionSort(alist):
for index in range(1, len(alist)):
currentvalue=alist[index]
position=index
while position>0 and

position-=1
alist[position]=currentvalue

[TheTenaciousE]

Wow I just noticed this Computer Science playlist, I'm going to be studying this in university next year, so this will be some nice preparation! Thanks a lot! =)

[kamaboko]

Sure, there may be a shorter (i.e., more dry way ) to do this, but the explanation is clear. Thanks.

[navneetbharadwaj]

please add more lectures on python programming as the content quality was amazing

[ayushmishra-oncs]

plz upload some more vidoes of i want to learn everything from a to z in python..and u teach awesome!

[rckd]

@mauroprovatos the part of the list to the left of index never decreases left-to-right when beginning the outer for loop (because the list is sorted from left to right). You can think of the inner while loop as marching what was originally list[index] to the left as far as it needs. For each step of that loop the same value is getting assigned from right to left. So list[i+1] == value (equals) will be true. If the left list part weren't already sorted then the algorithm wouldn't be correct.

[jasmeetsingh]

Back in the day when even python required 2 lines for swapping variables. :P

[BYZ]

please please please give more lectures on algorithms :)

[techguy]

This code doesn't work on my Apple device.

[mauroprovatos]

by list[i+1] = list [i
wont the initial value of list[i+1] be lost forevah?

[DrStevoXD]

a = [5, 1, 7, 2, 8, 3, 9]
a.sort()
print a

done.

[hkdobrev]

The if statement in the loop is obsolete. It could and should be included in the while condition. This way the break statement would be avoided.

[lesleymitchell]

I dont understand why you decrease i... it begins with value zero then later you minus 1... confused

[angeluffviiz]

Thank you so much for explaining this in detail. There's actually a minor problem with your code. The while loop doesn't break if the second item is greater than first item.
So one suggestion is that you decrement i by 1 at the end of the while loop besides the decrement of i within if function.

[Giorgio]

Is this available with strings instead of numbers?

[TimeDilationAuthority]

def sort(a):
A=[]
for i in range(len(a)):
A.append(min(a))
a.remove(min(a))
return A
this is even simpler

[BiranchiNarayanNayak]

I am looking for more sorting algorithms like Bubble Sort, Selection Sort, Merge Sort, Quick Sort ... etc