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Google L4-L6 Prep16 Topics

Learning to pass
the interview

Data structures and algorithms explained visually, without the math wall. Interactive diagrams, a Python playground, AI feedback, and progress tracking.

Google Interview Readiness0Just StartingStart practicing to build your scoreTry it now - no signupTwo Sum · easy

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)Real Python, real tests - it all runs in your browser.solution.py⌘↵ runLoading...OUTPUT

Run your code to see output

Not sure where to start?Follow the skill tree - learn concepts in the right order with prerequisites mapped out.View Learning Path0/16Topics Mastered0Challenges Solved0Active This Week

Data Structures

8 topics0% avg masteryBeginner

Arrays & Strings

avg O(n)space O(1)Mastery0%0/3 challengesEasy

Linked Lists

avg O(n)space O(1)Mastery0%0/2 challengesEasy

Stacks & Queues

avg O(1)space O(n)Mastery0%0/2 challengesEasy

Hash Tables

avg O(1)space O(n)Mastery0%0/2 challengesIntermediate

Binary Trees

avg O(log n)space O(h)Mastery0%0/2 challengesAdvanced

Graphs

avg O(V + E)space O(V + E)Mastery0%0/2 challengesIntermediate

Heaps / Priority Queues

avg O(log n)space O(n)Mastery0%0/1 challengesAdvanced

Tries

avg O(m)space O(n * m)Mastery0%0/1 challenges

Algorithms

6 topics0% avg masteryEasy

Sorting

avg O(n log n)space O(log n)Mastery0%0/1 challengesEasy

Binary Search

avg O(log n)space O(1)Mastery0%0/2 challengesIntermediate

Recursion & Backtracking

avg O(2^n)space O(n)Mastery0%0/1 challengesExpert

Dynamic Programming

avg O(n^2)space O(n)Mastery0%0/2 challengesIntermediate

BFS & DFS

avg O(V + E)space O(V)Mastery0%0/1 challengesIntermediate

Greedy Algorithms

avg O(n log n)space O(1)Mastery0%0/1 challenges

Concepts

2 topics0% avg masteryBeginner

Big-O Notation

avg N/Aspace N/AMastery0%0/1 challengesAdvanced

System Design Basics

avg O(1)space O(n)Mastery0%0/1 challenges

Learning to passthe interview