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All Problems

#	Status	Problem	Level	Completes	Likes
141		Reverse a Stack using recursion - In Place (Without using extra memory)	Hard	%	1
142		Convert Integer to Roman	Medium	%	0
143		String to Integer (AtoI - ASCII to Integer) - Recursive Solution	Medium	%	0
144		Longest contiguous character in a given String - O(N) Solution	Beginner	%	0
145		Convert Postfix to Infix Expression	Medium	%	0
146		Longest substring with at most two unique characters	Medium	%	0
147		Convert Infix to Prefix Expression	Medium	%	0
148		Find duplicates Characters in the given String	Beginner	%	0
149		Convert Infix to Postfix Expression	Medium	%	0
150		Evaluation of Infix expressions	Medium	%	0
151		Stack Java Class - Explained	Beginner	%	0
152		Merge K sorted Linked List - Using Priority Queue	Hard	%	0
153		Infix, Postfix and Prefix Notations/Expressions	Beginner	%	0
154		Count Set bits in a given Number	Beginner	%	1
155		Reverse a given number – Java Code	Beginner	%	1
156		Least Recently Used (LRU) Cache – Using HashMap and Doubly Linked List | Set 1	Hard	%	1
157		Valid Brackets – Part 2 | Stack Method	Beginner	%	0
158		Given two strings validate the output string	Beginner	%	0
159		Multiply with power of 2 without using pow() or * operator	Beginner	%	1
160		Find Number of reverse pairs in an array	Hard	%	1
161		Check if Given Number is power of 2.	Beginner	%	1
162		Calculate Log2n without using built-in function	Beginner	%	1
163		Check if two Strings are equal without using built-in function - Java	Beginner	%	0
164		Remove Vowels from a given String	Beginner	%	0
165		Swap two numbers using Bitwise XOR Operator	Medium	%	1
166		Find number of Distinct Permutations of a String	Medium	%	0
167		Divide with power of 2 without using pow() or / operator	Beginner	%	1
168		Left Shift (<<) and Right Shift (>>) Operators	Beginner	%	1
169		Convert Number to base 3 String Representation	Beginner	%	1
170		Graph – Count all paths between source and destination	Medium	%	1
171		Graph – Detect Cycle in a Directed Graph	Medium	%	1
172		Graph – Depth First Search in Disconnected Graph	Medium	%	1
173		Topological Sort	Medium	%	1
174		Graph – Depth First Search using Recursion	Beginner	%	1
175		Graph Implementation – Adjacency Matrix | Set 3	Beginner	%	1

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

Convert Integer to Roman

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

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

Find duplicates Characters in the given String

Convert Infix to Postfix Expression

Evaluation of Infix expressions

Stack Java Class - Explained

Merge K sorted Linked List - Using Priority Queue

Infix, Postfix and Prefix Notations/Expressions

Count Set bits in a given Number

Reverse a given number – Java Code

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

Valid Brackets – Part 2 | Stack Method

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

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 - Java

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

Graph – Detect Cycle in a Directed Graph

Graph – Depth First Search in Disconnected Graph

Topological Sort

Graph – Depth First Search using Recursion

Graph Implementation – Adjacency Matrix | Set 3

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