Sum Query in 2D Immutable Array Dynamic Programming

/ tusharroy25
github.com/mis...
github.com/mis...
Given a 2D matrix matrix, find the sum of the elements inside the rectangle defined by its upper left corner (row1, col1) and lower right corner (row2, col2).

[@Official-tk3nc]

Hope you all get placed in your dream company: All the best guys

[@tirushma]

No one can replace you....Who care about Attendance in NIT if Tushar Roy is here...!!!
#Placed in SAIL #Aapki Meharbaani

[@tirushma]

+Tushar Roy Qualified from Gate sir

[@tirushma]

+Tushar Roy thank you so much.....

[@vikasshivashankara878]

Thanks Tushar, I totally understood this algorithm hopefully i can apply in any problems involving using matrix sum 2d array.

[@AkankshaSingh-yu4lg]

Omg , finally i understood the algo , best explanation . Never knew that it was so easy.

[@shashankrajholavanalli2868]

You are too good at explaining Tushar. Keep it up :)

[@DK-ox7ze]

What's the logic behind calculating prefix sum for each cell? What's the intuition behind the formula you used?

[@shyamtripathy5084]

Awesome.. The code suggested by you was like 100 % faster in leetcode. The solution i thought was using a 3d matrix and used DP. I really appreciate this video

[@namanyourfriend1998]

Hello Tushar...Great video. I was curious about the case where the matrix is not immutable.

[@umeshchand2211]

Amazing tutorials ....wish you best of luck for mission-peace :)

[@harpercfc_]

Thank you :D finally understood this algo

[@Diptoredwan]

Hello +Tushar Roy , Your tutorials are very helpful. Thanks for these amazing tutorials. I would like to request for a tutorial on Suffix Automaton. :)

[@Diptoredwan]

Thanks :)

[@jlecampana]

Is there someone who can actually code this time efficient solution during an interview w/o having seen the problem before?

[@depression_plusplus6120]

Quite hard actually. Hopefully interviewers help a lot

[@ankushgats]

Thanks again Tushar. You made DP look so easy for me.

[@nayankhuman1043]

Thanks for the great explanation

my hero!! you are the best bro !! tks a lot

[@thatsit2397]

why he isn't active anymore?

[@priyankpande9]

Hi Tushar,
Your tutorials are very helpful.
If possible please cover these 2 questions -
1. All possible increasing subsequences of numbers in a linear array having gcd 1 of any length.
2. How to answer question when asked about searching/auto correction in a dictionary -
As per I know Trie can be a way but that is a prefix based solution
Or edit distance will take too much time to check with all the words available ?

[@GeraldoLopez]

saw three videos trying to explain the problem, yours by far is superior. thanks.

[@kunalkathpal7167]

Tushar Roy , i must say "fabulous explanation!!"

[@JayDonga]

What difficulty shall we face if we didn't allocate extra row and extra column in second matrix?

[@shiyadh4471]

Then we can't directly use the terms T[i-1][j], T[i][j-1] and T[i][j] in case of the elements in first row and columns(2,0,-3,4,,,6,5,2).
Right?

[@rlalduhsaka6746]

hello Tushar. can you please make some tutorials in fault tolerant systems?

[@ivanbogatyrev2388]

Great explanation! Thank you.

[@ranesh237]

Is this a floyd-warshall algorithm?

[@andreiivasko949]

Amazing, thanks Tushar!

[@normalpeople3441]

one of the best explanation thanks man..

[@stdiosus]

Спасибо!

[@musabbirahmedkhan7049]

way of teaching is the best

[@FinanceStoryTime]

Fantastic explanation!! Wow!!

[@ErfanHossainShoaib]

one of the great tutorial...

[@manishasinha6694]

Sir, your way of teaching is the best.. please suggest best site for coding?

[@tusharroy2525]

leetcode

[@ashishsinha8893]

leetcode and codeforces,geeksforgeeks

[@narendraparmar1631]

Thanks 😆

[@yamanshiekhdeia4778]

great job!

[@wukunliu1714]

big fam!!

[@daydreameravani]

Helps a lot!

[@judemartin8369]

Awesome !

[@surajch2678]

👏

[@shuvendubikash3792]

Will u please write the output of your program in comment inside the code that you provide in GitHub. As I am a C++ programmer I can not test your java code nd I have to write my own code, I am left with a little confusion whether my output is write or wrong. if u start doing so, it will be better for us.
thank you...