Google L4-L6 Prep
16 Topics
Learning to pass
the interview
Structured prep covering the data structures and algorithms big-tech interviews expect. Interactive visualizations, a Python playground, AI-powered feedback, and progress tracking.
Google Interview Readiness
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Solve a real Google interview question, right here
Given an array of integers `nums` and an integer `target`, return the indices of the two numbers that add up to `target`. Each input has exactly one solution. You may not use the same element twice.
Time:O(n)
Space:O(n)
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solution.py
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Data Structures
8 topics0% avg mastery
Beginner
Arrays & Strings
avg O(n)space O(1)
Mastery0%
0/3 challenges
Easy
Linked Lists
avg O(n)space O(1)
Mastery0%
0/2 challenges
Easy
Stacks & Queues
avg O(1)space O(n)
Mastery0%
0/2 challenges
Easy
Hash Tables
avg O(1)space O(n)
Mastery0%
0/2 challenges
Intermediate
Binary Trees
avg O(log n)space O(h)
Mastery0%
0/2 challenges
Advanced
Graphs
avg O(V + E)space O(V + E)
Mastery0%
0/2 challenges
Intermediate
Heaps / Priority Queues
avg O(log n)space O(n)
Mastery0%
0/1 challenges
Advanced
Tries
avg O(m)space O(n * m)
Mastery0%
0/1 challenges
Algorithms
6 topics0% avg mastery
Easy
Sorting
avg O(n log n)space O(log n)
Mastery0%
0/1 challenges
Easy
Binary Search
avg O(log n)space O(1)
Mastery0%
0/2 challenges
Intermediate
Recursion & Backtracking
avg O(2^n)space O(n)
Mastery0%
0/1 challenges
Expert
Dynamic Programming
avg O(n^2)space O(n)
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0/2 challenges
Intermediate
BFS & DFS
avg O(V + E)space O(V)
Mastery0%
0/1 challenges
Intermediate
Greedy Algorithms
avg O(n log n)space O(1)
Mastery0%
0/1 challenges
Concepts
2 topics0% avg mastery
Beginner
Big-O Notation
avg N/Aspace N/A
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0/1 challenges
Advanced
System Design Basics
avg O(1)space O(n)
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0/1 challenges