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
616 Count Substrings Divisible By Last Digit Hard
StringDynamic Programming
617 Count Substrings Starting and Ending with Given Character Medium
MathStringCounting
618 Count Substrings That Can Be Rearranged to Contain a String I Medium
Hash TableStringSliding Window
619 Count Substrings That Can Be Rearranged to Contain a String II Hard
Hash TableStringSliding Window
620 Count Substrings That Differ by One Character Medium
Hash TableStringDynamic Programming
621 Count Substrings That Satisfy K-Constraint I Easy
StringSliding Window
622 Count Substrings That Satisfy K-Constraint II Hard
ArrayStringBinary Search
623 Count Substrings With K-Frequency Characters I Medium
Hash TableStringSliding Window
624 Count Substrings With K-Frequency Characters II Hard
Hash TableStringSliding Window
625 Count Substrings with Only One Distinct Letter Easy
MathString
626 Count Substrings Without Repeating Character Medium
Hash TableStringSliding Window
627 Count Subtrees With Max Distance Between Cities Hard
Dynamic ProgrammingBit ManipulationTree
628 Count Symmetric Integers Easy
MathEnumeration
629 Count Tested Devices After Test Operations Easy
ArraySimulationCounting
630 Count the Digits That Divide a Number Easy
Math
Showing 616-630 of 3600
1 ... 40 41 42 43 44 ... 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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