Keshav Dev Sharma

code. break. learn. repeat.

backend/dev/security
building projects while grinding dsa.

js • python • react • flask • node.js

[Keshav Dev Sharma @KDSAMF]

I am working on a project
Will update soon.

If anybody use kotlin we can build together

[Keshav Dev Sharma @KDSAMF]

My application is on testing phase now .
Here is the glimpse
1st - summary of the notification on priority basis
2nd - automatic sensitive information like otp etc are hidden for the api.

[Shubh Jain @shubh19]

DSA Preparation Roadmap (From Zero to OA Ready)

1. Sliding Window: 3, 76, 209, 424, 567, 904
2. Two Pointers: 11, 15, 16, 18, 42, 167
3. Fast/Slow Pointers (Linked List): 141, 142, 19, 876, 160, 234
4. Binary Search on Sorted Data: 33, 34, 35, 153, 162, 704
5. Binary Search on Answer: 875, 1011, 410, 774, 1283, 1482
6. Hashing / Frequency Maps: 1, 49, 128, 217, 242, 347
7. Prefix Sum / Running Sum: 303, 560, 724, 930, 974, 523
8. Difference Array / Range Updates: 370, 1094, 1109, 1893, 1943, 2381
9. Monotonic Stack: 739, 496, 503, 84, 85, 901
10. Monotonic Queue / Deque: 239, 862, 1425, 1438, 1499, 1696
11. Heap / Top K: 215, 347, 692, 703, 973, 1046
12. Intervals: 56, 57, 252, 253, 435, 452
13. Greedy Scheduling / Sorting: 45, 55, 406, 621, 763, 134
14. Linked List Manipulation: 21, 23, 24, 25, 92, 138
15. Tree DFS: 104, 112, 113, 543, 124, 226
16. Tree BFS / Level Order: 102, 103, 199, 515, 637, 116
17. BST Problems: 98, 99, 230, 235, 450, 700
18. Backtracking Basics: 46, 47, 77, 78, 90, 39
19. Backtracking with Constraints: 40, 17, 79, 131, 51, 52
20. Graph BFS / DFS: 200, 695, 733, 994, 1091, 1254
21. Topological Sort / DAG: 207, 210, 802, 1462, 1203, 2115
22. Union Find / DSU: 547, 684, 1319, 1579, 990, 1202
23. Shortest Path: 743, 787, 1514, 1631, 1334, 1976
24. MST / Graph Greedy: 1584, 1135, 1168, 1489, 778, 1102
25. Trie: 208, 211, 212, 648, 677, 1268
26. Bit Manipulation: 136, 137, 191, 338, 268, 190
27. 1D DP Basics: 70, 198, 213, 322, 279, 300
28. Knapsack / Subset DP: 416, 494, 518, 474, 1049, 879
29. Grid DP: 62, 63, 64, 221, 931, 120
30. String DP / Sequence DP: 1143, 72, 115, 583, 97, 1312

How to use this list? 
- These numbers are Leetcode problem numbers
- Do 3 patterns at a time, not all 30 together.
- For each pattern, solve the first 2 to understand the idea, the next 2 to get repetition, and the last 2 to stretch yourself.
- After every pattern, write one reusable template from memory.
- Do not just “solve and move on.” Ask: what signal in the question pointed to this pattern?
- If you get stuck, revisit the same pattern after 3 to 4 days. Pattern recognition is built by spacing, not cramming.

[Keshav Dev Sharma @KDSAMF]

Solved Remove Nth Node From End of List on LeetCode.

A clean linked list problem using the two-pointer technique:

- Create a dummy node
- Move the right pointer n steps ahead
- Move both pointers together
- Remove the target node in one pass

#LeetCode #DSA

[Keshav Dev Sharma @KDSAMF]

Solved Reorder List on LeetCode

Loved this one! A nice mix of linked list concepts.

Approach:

- Find middle (fast & slow pointers)
- Reverse second half
- Merge alternately
#dsa #LeetCode

[Keshav Dev Sharma @KDSAMF]

Dear @IRCTCofficial
make your app scalable
During tatkal times it's already at high load.
- Let's say even if you got a chance to book a ticket during the window, Payments fails.
- Your app has a bug we need to login 2 times.

Trying for 2 days and still cannot get a ticket

[Keshav Dev Sharma @KDSAMF]

@cneuralnetwork https://t.co/8p0iSD8JeK

[Keshav Dev Sharma @KDSAMF]

@kaif9998 You don't need to 😉

[Keshav Dev Sharma @KDSAMF]

If anyone wants to be the beta tester for the app contact me 😉
@X
#tester #android #startup

[Keshav Dev Sharma @KDSAMF]

Was not posting lately due to shifting
But few new updates on the project

Feat: added logo
Added sorting based on high low and medium priority messages.
Added db so it can store messages until you delete it.

[Keshav Dev Sharma @KDSAMF]

Solved Sort Colors- leetcode

Today learned the new Algo: Dutch National Flag
#leetcode #dsa

[Keshav Dev Sharma @KDSAMF]

Stage2 of my application is completed

[Keshav Dev Sharma @KDSAMF]

Solved Square Of Sorted Array with Two approaches.

✔️ Square + Sort → O(n log n), O(1)
✔️ Two Pointers → O(n), O(n)
Both work, but the two-pointer approach trades space for speed.

That's the beauty of DSA: every optimization comes with a tradeoff
#leetcode #dsa

[Keshav Dev Sharma @KDSAMF]

Solved Leetcode - 11

Took me some time to understand why we move the shorter pointer instead of the taller one, but once it clicked the solution felt obvious 😂.

it is little similar to (https://t.co/YsOuJGHhpl)

O(n) Time
O(1) Space
Slowly getting better at DSA
#leetcode #dsa

[Keshav Dev Sharma @KDSAMF]

bro @striver_79, you are a literal gem. 😭😭
was stuck at this leetcode hard stack problem for atleast 3hrs. and just by watching you explain the algo i will remember the pattern forever dude.

[Keshav Dev Sharma @KDSAMF]

Today is my birthday and I am building a unified notification hub (app).

Let's see how it works out

[Keshav Dev Sharma @KDSAMF]

solved 3Sum - leetcode
solved by 2 ways:
1 => hashing based
2 => two pointer (with the help of @striver_79 )
#leetcode #dsa

[Keshav Dev Sharma @KDSAMF]

The first prototype is ready

[Keshav Dev Sharma @KDSAMF]

@RoseOnX9 Wait till the MITM attack happens and the middleman gets the adb shell 😔

[Keshav Dev Sharma @KDSAMF]

Which laptop should I buy around 80k