I am not even able to solve problems which i have solved in the past.I skipped permutation and combination in my high school.Is this problem because of the above mentioned reason or do i need to just practice more problems ? Please help, I did try to find about it on google, but didn't get much info. Also, It will be very helpful if someone can list some nice problems on it. Thanks in advance :)
practise
Can you please tell me if solving codeforces problems is enough or i need to solve problems from textbooks?
Just problems on PnC and related DP problems. No textbook needed. Just make sure that you understand editorials and concepts properly when you encounter them while solving problems.
If you want good combinatoric problems, I think AtCoder is the best place for it.
Thanks a lot.Does Atcoder has a feature to sort problems based on specific topic or do i have to search problems by reading it?
This might help — Atcoder Tags.
Nice, I did not know about that page.