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Top 20 Problems on Dynamic programming

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Top 25 Problems on Trees

Top 10 Problems on Bits Manipulation

Top 15 Problems in LinkedList

All Problems

# Status Problem video Level Completes Likes
392

Reverse a Stack using recursion - In Place (Without using extra memory)

Hard % 1
391

Check if given an edge is a bridge in the graph

Medium % 0
386

Convert Integer to Roman

Medium % 0
385

String to Integer (AtoI - ASCII to Integer) - Recursive Solution

Medium % 0
384

Grouping of Anagrams

Medium % 0
380

Count the number of nodes in a given binary tree

Beginner % 0
378

Longest contiguous character in a given String - O(N) Solution

Beginner % 0
377

Convert Postfix to Infix Expression

Medium % 0
373

Longest substring with at most two unique characters

Medium % 0
371

Convert Infix to Prefix Expression

Medium % 0
368

Max Flow Problem - Ford-Fulkerson Algorithm

Hard % 0
367

Sum of all Unique elements in a given array

Beginner % 0
365

Convert Infix to Postfix Expression

Medium % 0
364

Find three smallest elements in a given array

Beginner % 0
363

Evaluation of Infix expressions

Medium % 0
362

Stack Java Class - Explained

Beginner % 0
359

Merge K sorted Linked List - Using Priority Queue

Hard % 0
358

Infix, Postfix and Prefix Notations/Expressions

Beginner % 0
353

Reverse a given number

Beginner % 1
351

Least Recently Used (LRU) Cache – Using HashMap and Doubly Linked List | Set 1

Hard % 1
350

Find first three largest elements in a given array

Beginner % 0
344

Given two strings validate the output string

Beginner % 0
339

Multiply with power of 2 without using pow() or * operator

Beginner % 1
338

Find Number of reverse pairs in an array

Hard % 1
334

Dijkstra Algorithm Implementation – TreeSet

Hard % 0
330

Check if Given Number is power of 2

Beginner % 1
318

Calculate Log2n without using built-in function

Beginner % 1
313

Check if two Strings are equal without using built-in function

Beginner % 0
312

Remove Vowels from a given String

Beginner % 0
307

Swap two numbers using Bitwise XOR Operator

Medium % 1
305

Find number of Distinct Permutations of a String

Medium % 0
301

Divide with power of 2 without using pow() or / operator

Beginner % 1
298

Left Shift (<<) and Right Shift (>>) Operators

Beginner % 1
293

Convert Number to base 3 String Representation

Beginner % 1
277

Graph – Count all paths between source and destination

Medium % 1

Reverse a Stack using recursion - In Place (Without using extra memory)

Check if given an edge is a bridge in the graph

Convert Integer to Roman

String to Integer (AtoI - ASCII to Integer) - Recursive Solution

Grouping of Anagrams

Count the number of nodes in a given binary tree

Longest contiguous character in a given String - O(N) Solution

Convert Postfix to Infix Expression

Longest substring with at most two unique characters

Convert Infix to Prefix Expression

Max Flow Problem - Ford-Fulkerson Algorithm

Sum of all Unique elements in a given array

Convert Infix to Postfix Expression

Find three smallest elements in a given array

Evaluation of Infix expressions

Stack Java Class - Explained

Merge K sorted Linked List - Using Priority Queue

Infix, Postfix and Prefix Notations/Expressions

Reverse a given number

Least Recently Used (LRU) Cache – Using HashMap and Doubly Linked List | Set 1

Find first three largest elements in a given array

Given two strings validate the output string

Multiply with power of 2 without using pow() or * operator

Find Number of reverse pairs in an array

Dijkstra Algorithm Implementation – TreeSet

Check if Given Number is power of 2

Calculate Log2n without using built-in function

Check if two Strings are equal without using built-in function

Remove Vowels from a given String

Swap two numbers using Bitwise XOR Operator

Find number of Distinct Permutations of a String

Divide with power of 2 without using pow() or / operator

Left Shift (<<) and Right Shift (>>) Operators

Convert Number to base 3 String Representation

Graph – Count all paths between source and destination