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
2611 Number of Submatrices That Sum to Target Hard
ArrayHash TableMatrix
2612 Number of Subsequences That Satisfy the Given Sum Condition Medium
ArrayTwo PointersBinary Search
2613 Number of Subsequences with Odd Sum Medium
ArrayMathDynamic Programming
2614 Number of Substrings Containing All Three Characters Medium
Hash TableStringSliding Window
2615 Number of Substrings With Fixed Ratio Medium
Hash TableMathString
2616 Number of Substrings With Only 1s Medium
MathString
2617 Number of Times a Driver Was a Passenger Medium
Database
2618 Number of Times Binary String Is Prefix-Aligned Medium
Array
2619 Number of Transactions per Visit Hard
Database
2620 Number of Trusted Contacts of a Customer Medium
Database
2621 Number of Unequal Triplets in Array Easy
ArrayHash TableSorting
2622 Number of Unique Categories Medium
Union FindInteractiveCounting
2623 Number of Unique Flavors After Sharing K Candies Medium
ArrayHash TableSliding Window
2624 Number of Unique Good Subsequences Hard
StringDynamic Programming
2625 Number of Unique Subjects Taught by Each Teacher Easy
Database
Showing 2611-2625 of 3600
1 ... 173 174 175 176 177 ... 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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