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Dynamic Prograahh..f
Dynamic Prograahh..f

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Day 2

Today I solved the following problems from Striver DSA sheet. Also today I was able to figure out a dynamic programming solution on my own so I am very psyched about it.

PROBLEM 1: Search in a 2-D matrix: Took some time, but was able to figure out the most optimal approach, O(log(rows * log(cols))

PROBLEM 2: Implement pow function: Solved it optimally in O(log(n))

PROBLEM 3: Majority Element I: Was able to figure out O(N) time and space solution but learnt about Bayers' Voting Algorithm to reduce space to O(1)

PROBLEM 4: Majority Element II: Almost same concept as previous

PROBLEM 5: Reverse Pairs: Had solved 'Count Inversions' yesterday, hence was able to solve it on my own.

PROBLEM 6: Unique Paths: First solved it using DFS approach which had exponential time complexity. Then was able to boil it down to O(m * n) using memoization dynamic programming on the recursion.

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