Master DSA Topics - January, 2026

Practice problems across 75+ categories

All Coding Problems

Practice coding problems across all companies and topics 3600 problems | 879 Easy | 1856 Medium | 842 Hard

# Problem Difficulty Topics
631 Count the Hidden Sequences Medium
ArrayPrefix Sum
632 Count the Number of Arrays with K Matching Adjacent Elements Hard
MathCombinatorics
633 Count the Number of Beautiful Subarrays Medium
ArrayHash TableBit Manipulation
634 Count the Number of Complete Components Medium
Depth-First SearchBreadth-First SearchUnion Find
635 Count the Number of Computer Unlocking Permutations Medium
ArrayMathBrainteaser
636 Count the Number of Consistent Strings Easy
ArrayHash TableString
637 Count the Number of Experiments Medium
Database
638 Count the Number of Fair Pairs Medium
ArrayTwo PointersBinary Search
639 Count the Number of Good Nodes Medium
TreeDepth-First Search
640 Count the Number of Good Partitions Hard
ArrayHash TableMath
641 Count the Number of Good Subarrays Medium
ArrayHash TableSliding Window
642 Count the Number of Good Subsequences Medium
Hash TableMathString
643 Count the Number of Houses at a Certain Distance I Medium
Breadth-First SearchGraphPrefix Sum
644 Count the Number of Houses at a Certain Distance II Hard
GraphPrefix Sum
645 Count the Number of Ideal Arrays Hard
MathDynamic ProgrammingCombinatorics
Showing 631-645 of 3600
1 ... 41 42 43 44 45 ... 240

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public class MyFirstJavaProgram { Edit & Run

   /* This is my first java program.
    * This will print 'Hello, World!' as the output
    */

   public static void main(String []args) {
      System.out.println("Hello, World!"); // prints
   }
}

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