GrokkingTheCodingInterviewPatterns

This is a collection of coding problems that summarize the grokking the coding interview patterns course on educative.io.

Pattern: Two Pointers

• https://leetcode.com/problems/two-sum/

• https://leetcode.com/problems/remove-duplicates-from-sorted-array/

• https://leetcode.com/problems/squares-of-a-sorted-array/

• https://leetcode.com/problems/3sum/

• https://leetcode.com/problems/3sum-closest/

• https://leetcode.com/problems/3sum-smaller/

• https://leetcode.com/problems/subarray-product-less-than-k/

• https://leetcode.com/problems/sort-colors/

• https://leetcode.com/problems/4sum/

• https://leetcode.com/problems/backspace-string-compare/

• https://leetcode.com/problems/shortest-unsorted-continuous-subarray/

Pattern: Fast & Slow pointers

• https://leetcode.com/problems/linked-list-cycle/

• https://leetcode.com/problems/linked-list-cycle-ii/

• https://leetcode.com/problems/happy-number/

• https://leetcode.com/problems/middle-of-the-linked-list/

• https://leetcode.com/problems/palindrome-linked-list/

• https://leetcode.com/problems/reorder-list/

• https://leetcode.com/problems/circular-array-loop/

Pattern: Sliding Window

• https://leetcode.com/problems/maximum-subarray/ # Close enough

• https://leetcode.com/problems/minimum-size-subarray-sum/

• https://leetcode.com/problems/longest-substring-with-at-most-k-distinct-characters/

• https://leetcode.com/problems/fruit-into-baskets/

• https://leetcode.com/problems/longest-substring-without-repeating-characters/

• https://leetcode.com/problems/longest-repeating-character-replacement/

• https://leetcode.com/problems/max-consecutive-ones-iii/

• https://leetcode.com/problems/permutation-in-string/

• https://leetcode.com/problems/find-all-anagrams-in-a-string/

• https://leetcode.com/problems/minimum-window-substring/

• https://leetcode.com/problems/substring-with-concatenation-of-all-words/

Pattern: Merge Intervals

• https://leetcode.com/problems/merge-intervals/

• https://leetcode.com/problems/insert-interval/

• https://leetcode.com/problems/interval-list-intersections/

• https://leetcode.com/problems/meeting-rooms-ii/

• https://leetcode.com/problems/employee-free-time/

Pattern: Cyclic Sort

-- Cyclic Sort

-- https://leetcode.com/problems/missing-number/

-- https://leetcode.com/problems/find-all-numbers-disappeared-in-an-array/

-- https://leetcode.com/problems/find-all-duplicates-in-an-array/

-- combine https://leetcode.com/problems/find-the-duplicate-number/ and https://leetcode.com/problems/missing-number/

-- https://leetcode.com/problems/first-missing-positive/

-- https://leetcode.com/problems/kth-missing-positive-number/

Pattern: In-place Reversal of a LinkedList

-- https://leetcode.com/problems/reverse-linked-list/

-- https://leetcode.com/problems/reverse-linked-list-ii/

-- https://leetcode.com/problems/reverse-nodes-in-k-group/

-- https://leetcode.com/problems/rotate-list/

Pattern: Tree Breadth First Search

-- https://leetcode.com/problems/binary-tree-level-order-traversal/

-- https://leetcode.com/problems/binary-tree-level-order-traversal-ii/

-- https://leetcode.com/problems/binary-tree-zigzag-level-order-traversal/

-- https://leetcode.com/problems/minimum-depth-of-binary-tree/

-- https://leetcode.com/problems/inorder-successor-in-bst/ # Close, not exact

-- https://leetcode.com/problems/populating-next-right-pointers-in-each-node/ # Close, grokk assumes non-perfect tree

-- https://leetcode.com/problems/binary-tree-right-side-view/

Pattern: Tree Depth First Search

-- https://leetcode.com/problems/path-sum/

-- https://leetcode.com/problems/path-sum-ii/

-- https://leetcode.com/problems/sum-root-to-leaf-numbers/

-- https://leetcode.com/problems/check-if-a-string-is-a-valid-sequence-from-root-to-leaves-path-in-a-binary-tree/description/

-- https://leetcode.com/problems/path-sum-iii/

-- https://leetcode.com/problems/diameter-of-binary-tree/

-- https://leetcode.com/problems/binary-tree-maximum-path-sum/

Pattern: Two Heaps

-- https://leetcode.com/problems/find-median-from-data-stream/

-- https://leetcode.com/problems/sliding-window-median/

-- https://leetcode.com/problems/ipo/

-- https://leetcode.com/problems/find-right-interval/

Pattern: Subsets

-- https://leetcode.com/problems/subsets/

-- https://leetcode.com/problems/subsets-ii/

-- https://leetcode.com/problems/permutations/

-- https://leetcode.com/problems/letter-case-permutation/

-- https://leetcode.com/problems/generate-parentheses/

-- https://leetcode.com/problems/generalized-abbreviation/

-- https://leetcode.com/problems/different-ways-to-add-parentheses/

-- https://leetcode.com/problems/unique-binary-search-trees-ii/

-- https://leetcode.com/problems/unique-binary-search-trees/