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Data Structures & Algorithms

The round that decides everything

Pattern-first DSA with optimal time/space solutions in C++, Java & Python. Two tracks: placd 100 (most-asked) and Blind 75 (fundamentals).

  • placd 100
  • Blind 75
  • Patterns, not rote
  • Editorial solutions
  • Progress tracking

Sample questions

  • Two Sum
    Asked at Amazon
    Easy
  • Longest Substring Without Repeating
    Asked at Flipkart
    Medium
  • Merge K Sorted Lists
    Asked at Google
    Hard
  • Number of Islands
    Asked at Microsoft
    Medium
  • Trapping Rain Water
    Asked at Uber
    Hard
Unlock full set

Master DSA, pattern by pattern

21 categories, 3,000+ problems with optimal editorial solutions in C++, Java & Python. Start with placd 100 or Blind 75.

Core data structures

Arrays & Hashing
300 problems
Free
Linked Lists
43 problems
Trees
111 problems
Stacks
77 problems
Free
Queues
25 problems
Heaps
64 problems

Algorithm patterns

Two Pointers
30 problems
Free
Sliding Window
52 problems
Binary Search
30 problems
Dynamic Programming
122 problems
Greedy
51 problems
Sorting & Searching
87 problems

Advanced topics

Graphs
156 problems
Tries
33 problems
Matrix
68 problems
Bit Manipulation
45 problems
Intervals
16 problems
Math & Geometry
77 problems