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
646 Count the Number of Incremovable Subarrays I Easy
ArrayTwo PointersBinary Search
647 Count the Number of Incremovable Subarrays II Hard
ArrayTwo PointersBinary Search
648 Count the Number of Infection Sequences Hard
ArrayMathCombinatorics
649 Count the Number of Inversions Hard
ArrayDynamic Programming
650 Count the Number of K-Big Indices Hard
ArrayBinary SearchDivide and Conquer
651 Count the Number of K-Free Subsets Medium
ArrayMathDynamic Programming
652 Count the Number of Powerful Integers Hard
MathStringDynamic Programming
653 Count the Number of Special Characters I Easy
Hash TableString
654 Count the Number of Special Characters II Medium
Hash TableString
655 Count the Number of Square-Free Subsets Medium
ArrayMathDynamic Programming
656 Count the Number of Substrings With Dominant Ones Medium
StringEnumeration
657 Count the Number of Vowel Strings in Range Easy
ArrayStringCounting
658 Count The Number of Winning Sequences Hard
StringDynamic Programming
659 Count The Repetitions Hard
StringDynamic Programming
660 Count Total Number of Colored Cells Medium
Math
Showing 646-660 of 3600
1 ... 42 43 44 45 46 ... 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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