GitHub Coding Interview Questions

Showing 12 problems of 26

• #1easyfoundational

  1. Two Sum

  Find indices of two numbers in an array that sum to a target — GitHub uses this to gauge hash-map intuition before diving into Git ref lookup problems.

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• #2easyfoundational

  2. Valid Parentheses

  Determine if a string of brackets is balanced — GitHub uses this as a warm-up before diving into nested merge conflict markers and diff hunk delimiters.

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• #3easyfoundational

  3. Merge Two Sorted Lists

  Merge two sorted linked lists into one sorted list — GitHub treats this as the toy version of merging two sorted commit-date streams during git log --merge.

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• #4easyfoundational

  4. Remove Duplicates from Sorted Array

  Remove duplicates in-place from a sorted array — GitHub uses this as the entry-level analogue to dedup-ing sorted SHA streams in the packfile delta index.

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• #5easyfoundational

  5. Remove Element

  Remove all occurrences of a value from an array in-place — GitHub's lead-in to pruning broken refs from a packed-refs file without reallocating.

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• #6easyfoundational

  6. Search Insert Position

  Return the index at which a target would be inserted in a sorted array — GitHub's warm-up for the binary search inside the pack-index .idx fan-out table.

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• #7easyfoundational

  7. Maximum Subarray

  Find the contiguous subarray with the largest sum — GitHub uses this Kadane warmup before stepping into hunk-coalescing scoring in their diff renderer.

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• #8easyfoundational

  8. Plus One

  Increment a number represented as a digit array by one — GitHub's tiny entry to BigInt carry handling, mirroring the version-counter bump in tag-name auto-increment scripts.

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• #9easyfoundational

  9. Merge Sorted Array

  Merge two sorted integer arrays in place into nums1 — GitHub's setup for the three-way merge core: writing from the back to avoid clobbering unread input.

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• #10easyfoundational

  10. Binary Tree Inorder Traversal

  Return the inorder traversal of a binary tree's node values — GitHub's lead-in to traversing the parent-DAG of a commit history in chronological order.

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• #11easyfoundational

  11. Same Tree

  Determine if two binary trees are identical — GitHub's stand-in for SHA-equality checks across two commit subtrees in a fast-forward verification.

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• #22easyfoundational

  22. Symmetric Tree

  Check whether a binary tree is a mirror of itself using recursive or iterative paired traversal, a BFS/DFS tree skill GitHub tests in screening rounds.

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