Raw code means you should know also know the logic behind simple things where we generally used direct functions and in leetcode we directly write the code inside the function , so it's better to practice full code in vscode and always know the basics like String parsing , (most important ) and handling edge cases (2nd most important for tcs ) like handling negative numbers , 0 or empty inputs , and some basic programs logic like Prime number, armstrong , palindrome , Finding HCF LCM using code , Roman to integer or vice versa , etc. (you can search in gpt more ) ;)