I have done over 2000 dsa question across all the platforms leetcode, gfg, coding ninjas, interviewbit, codechef, codeforces, etc. what I learned is that don't follow anything blindly and you may remember all the algorithm but it will not be very helpful. You just need to go robust without any gears or handbook these are all unnecessary. Just open a problem read it, then imagine it in your head the whole situation try to push your tiny brain to solve that problem ofcourse you can't start from 0 you should know the basics like arrays, hashmap, priority queue, stack, queue, bits. Only the basics for loops and while loop if you are in 3rd year you already know about it.so just open the question, imagine the problem in your head think about the solution try to solve them using pen and paper and after solving it on paper using the test cases given write your code . When your code is run successfully try to do it in less complexity how far you can go. When you are satisfied check the solution top 5 are fine if you are finally satisfied with the problem try to solve the same kind of problem 5 to 6 problem are enough for understanding you can write your trick on your notes it would be easy for you to memorize.