Foundations #02 - Recursion → Memo → Table (DP ka engine)

Track: Foundations

Isi ek chhote sawaal ko, fib(n) kitna hota hai, chaar tareeke se solve karke dikhaya hai: seedha dohraav, ek likhi-hui yaadasht wala tareeka, ulta bhara hua table, aur sabse halka do-dabbon wala version.

Before you start. Foundations #01 se itna kaafi hai: jab size double hoti hai aur kaam bhi double ho jaata hai, use exponential kehte hain, aur wo bahut tezi se na-chalne-laayak ho jaata hai. Yahi doubling is lesson mein recursion ke andar chhupi milegi - dekhoge kaise.

DP koi jaadu nahi - sirf recursion + ek notebook. Ye board recursion ki basic se leke bottom-up DP tak, ek hi dhaage mein le jaata hai. Clinic #02 - Climbing Stairs, Clinic #03 - Coin Change, Clinic #21 - Unique Paths aur Clinic #22 - Longest Common Subsequence - sabhi isi engine pe chalte hain.