Google Coding Interview Questions
26 Google coding interview problems with full optimal solutions — 2 easy, 13 medium, 11 hard. Every problem ships with multiple approaches (brute-force first, then the optimal), complexity tables for each, company-specific tips on what an Google interviewer values, and a FAQ section.
Showing 2 problems of 26
- #1easyfoundational
1. Two Sum
Two Sum is Google's canonical warm-up: given an integer array and a target, return the indices of the two numbers that add up to the target. The interviewer is grading your willingness to narrate the space-for-time tradeoff before jumping to the optimal.
4 free resourcesSolve → - #20easyfoundational
20. Valid Parentheses
Given a string of brackets, return true if every opener has a matching, correctly-nested closer. Google asks this to confirm you can model push/pop state with a stack and articulate why the LIFO property is what makes the problem cleanly solvable.
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