1)Pickup a programming language , preferably C++ .
2)Focus heavily on loops , conditions and basic logics as they are going to build your foundation .
3)Preferably , solve 100+ C++ problems from sitesbay (
https://www.sitesbay.com/cpp-program/index)
4) Watch videos of Sir Saurabh Shukla or EasyTuts4u for C++ if you have doubt in some concept .
5) Now , to improve the real algorithmic skill , you must solve 40-50 problems from this section of Hackerrank : -
https://www.hackerrank.com/domains/algorithms?filters%5Bstatus%5D%5B%5D=unsolved&filters%5Bskills%5D%5B%5D=Problem%20Solving%20%28Basic%29&filters%5Bdifficulty%5D%5B%5D=easy&filters%5Bsubdomains%5D%5B%5D=warmup&filters%5Bsubdomains%5D%5B%5D=implementation&filters%5Bsubdomains%5D%5B%5D=strings&filters%5Bsubdomains%5D%5B%5D=arrays-and-sorting&filters%5Bsubdomains%5D%5B%5D=search&filters%5Bsubdomains%5D%5B%5D=greedy&filters%5Bsubdomains%5D%5B%5D=dynamic-programming&badge_type=problem-solving
6)Remember , every problem has a solution on youtube , or you can see the editorial of problem on Hackerrank and many people discussing the same problem in the discuss section of a problem for Hackerrank . Apply same protocols for LeetCode , Codeforces and Codechef .
7)Now, is the time to focus on sorting , searching , a bit of greedy algorithms , string problems and hashing concepts . Large portion of problems you face in contest or interviews will overlap with these topics in one way or the other . So make these super strong , thats the secret!
8)For strings , try these problems :
i)
https://www.hackerrank.com/domains/algorithms?filters%5Bdifficulty%5D%5B%5D=easy&filters%5Bdifficulty%5D%5B%5D=medium&filters%5Bsubdomains%5D%5B%5D=strings
ii)
https://450dsa.com/string
iii)
https://leetcode.com/explore/interview/card/top-interview-questions-easy/127/strings/883/
iv)
https://leetcode.com/discuss/study-guide/1333049/Collections-of-string-questions-pattern-for-upcoming-placement-2021
9)For sorting , searching and hashing :
Important :
https://leetcode.com/discuss/interview-question/313216/Binary-search-Interview-Questions
i)shorturl.at/bxEJY
ii)
https://www.geeksforgeeks.org/top-20-hashing-technique-based-interview-questions/
iii)
https://450dsa.com/array
iv)
https://450dsa.com/search_sort
10)For sliding window and 2 pointers technique :
https://leetcode.com/list/x17aw7vm/ ,
https://leetcode.com/articles/two-pointer-technique/
You can find videos on different problems for all these topics on these good youtube channels :
(Please learn to search like this : xyz channel , xyz topic and you will get what you were looking for)
1)
https://www.youtube.com/c/CodeLibrary
2)
https://www.youtube.com/c/Pepcoding
3)
https://www.youtube.com/c/takeUforward
Now , you have passed the beginner level , now to reach intermediate level in DSA , I will be posting a new answer .