Maximum Sum SubArray (Kadane's algorithm) (Largest Sum Contigous SubArray)
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- čas přidán 21. 05. 2017
- Find the subarray with the maximum sum in an array. The solution is given by the Kadane's algorithm. Also called Largest Sum Contigous SubArray.
I love the way how innocently he teaches.
Best Explanation of Kadane's Algo I have ever seen. The most important thing that you explained the algo into two parts -
1. Find the greatest sum
2. Find the starting and ending indices of subarray containing the max sum
Thank you so much for posting this videos! You have such clear explanations!
After wandering in a lot of youtube channels, eventually I've found the best explanation here. Thanks.
The way you explain is so clear. Thanks man.
(2 Line solution ) :-
int Kadane(int[] arr){
int localmax=arr[0];
int globalmax=arr[0];
for(int i=1;i
nice one
What's n here? If it is the length of the array, I get 22 for the above array that Vivekanand has used for the tutorial. Did you try using it before posting the 2-line answer?
Superb solution ☺️😃 enjoy 🤠
Can you explain this solution ?
Thank you for explaining the Maximum Sum Subarray algorithm in such an easy way. You are really good teacher! Keep up the good work!!!
one n only one best explaination of kadane's algo
brilliant explanation! the big thing is he makes it much easier to understand. thanks a lot.
You are great Sir! You make so simple with your extraordinary explanation! Thank you very much!!!
Great work man. Brilliant explanation. Please keep doing more videos. hope your channel grows.
Great explanation, I love it. One small simplification may be that max_so_far can be initialized to zero, rather than a[0]. Another advantage of making that change is that if the array is zero-length (size==0) you won't be accessing invalid memory.
you can handle an empty array with a base case that checks for an empty array and simply returns (i.e. if (arr.length === 0) return). If you initialize max_so_far to 0, a test case of [-2] (or any negative number) will fail. I used [-2] as an example because that's the test case I failed on Leetcode lol
best explanation among all videos on this topic on youtube. thank you !
Thanks Sanket..!
Best explanation that i have seen for this algo
awesome explanation sir, very very helpful, thanks a lot for this tutorial 👍👍👍👍🙂🙂🙂🙂
Bahut dino se struggle kr rha tha...lekin aaj samaj mei aa gaya. Thanx...
Thank you. You made tough problem, easy. :)
Best vedio I have ever seen for this solution 👍👍👍👍👍👍
Very good explanation. You're that favorite teacher kind of person! :)
han rat lo ise
czcams.com/video/motMHIXMmzk/video.html
finally i got the video by which i have understood this concept very easily.
Thank you so much ! your explanation is so helpful.
the way u explain is crystal clear, thank nu so much @vivek.
You made things understand easier
Great , Great simply you explain I understand, keep doing it , I want learn more algorithm topic probmel
Nice explain sir before watching this video i was confused that what the meaning of this algo but now cleared thanks a lot sir
I've seen this problem posted as a dynamic programming problem on Leetcode. I like this way better though. Is there any argument to do DP over this way?
Nice, Very Detailed!
best explanation of kadane algo
Great Explanation, make some more videos. Thanks
I think for efficient subarray it should be **if(max_ending_here
After seeing this video, I feel your one of the LC problems god!!!
Explained well!
Any idea about how to convert the finding the start index and end index into 2 D array ?
Very Well Explained :)
Great Explanation.
Good work. Easy to learn. Thank you..
Thanks man!
Best way to explain max sub array prob thanks
The second if condition is the core of this algo.
Nice explanation sir...You have great patience which is must for a programmer.
Regarding this example,we can take a lesser size array to save time.
Thank you sir for explaining in such a easy way 🙏
Thanks a lot lot sir..you explain us so well
you are simple and great....plzz provide some good and tuff DP problems ...:)
Nice Explanation sir...
Please upload more videos on Dynamic Programming..!!
very helpful , thank you
What if all elements are negative value? How do you dandle max_ending_here < 0 ? How would you track indices?
Above algorithm will not work if all the elements are negative. Please refer : www.techiedelight.com/maximum-subarray-problem-kadanes-algorithm/
This info is very helpful...
Solution is trivial. Return an empty array. Sum of all elements is zero (since there are no elements). 0 is strictly greater than any combination of negative numbers. You could create a subroutine to scan the array and return this result if this is the case. Total running time should be O(2n) which is still O(n).
Then just take the element with with highest value in all negative numbers
@@komuravellyvenky this code also fails if array is [-1]
nice explanation!!
Nice Work, Thank you Sir
thank you
Will this algorithm work for an input array {5, -2, -1, 3, -4}. Just a second set of eyes to verify we get the result as maximum length of the subarray is 4. Please help!
Great work Sir. Nice explanation.
Thanks Tanuj.
can we print the largest sub-array that was found , using Kadane algo?..we can get the end point of that sub-array but how do we get its starting point.
Great work
Hi Vivekanan sirji, you are doing a great job..
I have watched some of your other videos too and must say they are simply awesome and to the point..
It will be even better if you could organize your uploaded videos into a playlist, it will direct the users to your other videos.... just a suggestion :)
well said.it ll be great if a playlist is created topicwise.Your tutorial is awesome sir
Yes shobhit i will make it...! Thanks ....!
Yes srinidhi ...will make it..!
thank you best explanation❤❤
Very good explanation sir
Good explanation
Thanks for explanation
very well done
Thanks Sagar Bhau...!
Can you please make a video on Largest subarray with equal number of 0s and 1s with O(N) time complexity and also please make a video on Maximum Product Subarray?
What if we do not have any negative number present in the array?
One more observation ... What if the array consists entirely of negative values? This algorithm will report start and end both zero, which is a subarray of length 1. It seems like it may be better, in general, for the result to be reported as a start index and a length (rather than end index). Then the correct answer in this case (all elements negative) is start = zero (or really anything), length = zero. I implemented this here: codepad.org/irM2hs1b
Nice one..Yes need to do like 1.5x or 2x..lol...But great presentation!!
What will happen if there are no negative numbers in the array?
Nice Video. Well structured. Liked the way you simplified the solution in 2 parts.
1) find the max sum
2) look for index
Nice work thank you.....
Thanks Manoj..!
Thnks sir it was very detailed explanation
Algorithm tracing != Explaining
Thank You
Awesome 👍
What if all the elements in the array is set to 0?
If my array is -5 -4 -3-1 -2 will this algo work?
your understanding of the problem is Bad.....
The way I see the problem is 3 cases : Life Hope and Death.
We'll take 2 sum variables' : prev_sum and current_sum.
Life is when we encounter only positive number: we will update prev_sum in this case
Hope is when we encountered a negative number but that negative number has not made my current sum less than zero so there is still hope that some next number may repair the damage done by the negative number. : we will update prev_sum when current_sum > prev_sum
Death is when the current sum becomes negative .....so now in this case we have re-initialize the starting point for calculating current sum
Below is my smart : : code
public static int findLargestSum(int a[]) {
int end = 0;
int current_sum = 0;
int prev_sum = 0;
while (end < a.length) {
current_sum += a[end];
if (current_sum < 0) { // death case
current_sum = 0;
}
if (current_sum > prev_sum) {
prev_sum = current_sum;
}
end++;
}
return prev_sum;
Keep it up
Sir you are awesome
why we equalise the max ending here to zero on second if
Hello Sir,
Can you please post video for solution of "maximum/minimum element from each sub-array of size 'k'" in O(n) ?
Thanks in advance.
if I will take only all elements negative except first then this code will not give the index of maximum subarray you can check it
Sir will the algorithm work if the maximum sum is negative?
Carry On...
Good explanatiin
will this algo works if we have the max sum in -ve itself....i.e if all the elements of the array are -ve, then what to do ?
No this works for everything
Thank you sir 🙏
sir thank you very much.i am from bangladesh.
awesome
perfect explenentation
grt sir .But this question was asked in my interview but i was not aware of this algo.But i gave a brute force solution by using two loops O(n^2).Here in this algo it is taking linear time o(n). Can we make it to O(log n) by using divide and conquer approach?
if the array is not sorted , we cannot do it in o(logn) . in other way , meaning only binary search will make time complexity of o(logn) and binary search will work only on sorted arrays .
You could divide and conquer in O(nlog(n)) recursively Find max on left, max on right, and find max that crosses the midpoint
Hello sir, can u make a video on Z algorithm for String search.
Longest Palindrome in a string
thanks!!!!!!!!
Thanks Vivek
please do video , print all different simple cycle in undirected graph . 🙌
yes sure ...very soon..!
NO need to check whether the sum is less than zero or not else do check whether calculated sum is greater than added element or not ? and rest will be same .
Sir plz explain dijkstras algorithm with snippet like this sir
thanks
HI Sir, Can you upload Matrix related java programs with algorithm explanation ... Please sir
sir how to approach the algo please teach that not as ratta mar study
Set the speed to 1.5, Thank me later:)
Thank u bro :)
Thank u bro :)
Lol ! Thank you bro :)
Thank U Bro :)
i suggest 2.0x
Please do a video Tutorial on Flatten a Linkedlist, Union of 2 Linkedlist
Yes sure I will do it..!
Hi Vivekanand,
Please help me with video to print given matrix in diagonal order
Thanks
Yes i will upload the matrix video very soon..!
Vivek, the way you explain is crystal clear by giving examples. Keep up the good work. God Bless.
What if all values are negative?????
it will return the greatest negative number. So if you have an array = [-6, -5, -20, -1], it will return -1
@@compeng2013 No it is going to return 0, we need to modify the code little bit
Just take the highest elment in the negative no