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SCHOOL (4)
BASIC (274)
EASY (404)
MEDIUM (204)
HARD (17)
- Rotate Array
- First Digit of Product of Numbers
- Sort String
- Print Linked List
- Count Linked List Nodes
- Power of Four
- Size of Binary Tree
- Count Leaves in Binary Tree
- Postorder Traversal
- Implement stack using array
- Queue using Linked List
- Add two fractions
- Replace all 0's with 5
- Replace all 0's with 5
- Count zeros in a sorted matrix
- Preorder Traversal
- First Occurence
- Sum Except First and Last
- Search a node in BST
- Remainder with 7
- Palindromic Array
- Multiply Matrices
- Peak element
- Linked List Insertion At End
- C++ Functions (Sum of numbers) | Set 1
- Minimum element in BST
- Anagram of String
- Is Linked List Length Even?
- Identical Linked Lists
- Modular Node
- Sum of Binary Tree
- Insert in Middle of Linked List
- longest substring containing '1'
- Count Non-Leaf Nodes in Tree
- Start Coding
- Logical Operators
- Sort and Reverse Vector
- Front to Back
- Stack designer
- Decimal to binary
- Bit Difference
- Binary Array Sorting
- Check if a string is Isogram or not
- Binary String
- Most Frequent Character
- Remove common characters and concatenate
- Sum of numbers in string
- Reverse a String
- Keypad typing
- First n Fibonacci
- C++ Hello World
- Find second largest element
- Minimum Product of k Integers
- Merge and Sort
- Multiply Array
- Rearranging array
- Count number of elements between two given elements in array
- Sum of Array
- Sum of Natural Numbers
- Searching in an Array
- Doubling the value
- Count pair sum
- Elements before which no element is bigger
- Remove consonants from a string
- Balanced Array
- Sort the Half Sorted
- At least two greater elements
- Type of array
- Sort a String
- Anagram Palindrome
- Sort The Array
- Alternative Sorting
- Check if divisible by 11
- Check if divisible by 4
- Remove all characters other than alphabets
- Maximum product of two numbers
- Value equal to index value
- Check String
- Convert a list of characters into a String
- Confused pappu
- Remove characters from alphanumeric string
- Segregate Even and Odd numbers
- Odd to Even
- Count of camel case characters
- Maximum triplet sum in array
- Count Pairs Odd Xor
- The problem of identical arrays
- Sum of alternate product
- Reverse sub array
- Immediate Smaller Element
- Sum of distinct elements
- Count the characters in each word in a given sentence
- Uncommon characters
- Sum of all sub-sequences of a number
- Quick Left Rotation
- Swap kth elements
- Stable Sort and Position
- Duck Number
- Lower case to upper case
- Remove repeated digits in a given number
- Remove Spaces
- Repeated Character
- Replace the Bit
- First 1 in a Sorted Binary Array
- Length of Last word
- Find the Number which contain the digit d
- Missing number in shuffled array
- Max and Min Product from 2 Arrays
- Elements in the Range
- Display longest name
- Last index of One
- Distinct Adjacent Element
- Making elements distinct
- Floating point number even or odd
- Sort the string in descending order
- Front-Back Transformation - copy
- Merge two strings
- Last duplicate element in a sorted array
- Largest Element in Array
- Rotate Array by One
- Game with nos
- Exceptionally odd
- Jay's Apples
- Split Strings
- Array Subset
- Rotating an Array
- Product is even or odd?
- Remove Duplicates from unsorted array
- Minimum sum of two elements from two arrays
- Even occurring elements
- Minimum number to form the sum even
- Count of smaller elements
- Min and Max in Array
- Multiply left and right array sum
- Positive and negative elements
- Extract Maximum
- Smallest number repeating K times
- Print first letter of every word in the string
- Boolean String Value
- Last index of a character in the string
- Good or Bad string
- Remove character
- Red OR Green
- Convert String to LowerCase
- Program to print reciprocal of letters
- No of Carry Operations
- C++ Basic Data types
- Factors Sum
- Difference between highest and lowest occurrence
- GCD of Array
- GCD of two numbers
- Find unique element
- Addition of Two Numbers
- C++ Input / Output
- 1s Complement
- Odd or Even
- Check set bits
- One's Complement
- XOR of all elements
- The OR Gate
- The AND Gate
- Check an Integer is power of 3 or not
- Check for Power
- Even Odd Sum
- Even-Odd turn game
- Factor OR Multiple
- Check if divisible by 36
- Odd Divisors
- Java Hello World
- Java Input/Output
- Smallest power of 2 greater than or equal to n
- Strong Numbers
- Count digits in given number N which divide N
- Full Prime
- Check if divisible by 5
- Check if a number can be expressed as x^y
- Sum of Digits Prime/Non-Prime
- LCM And GCD
- LCM of given array elements
- Small Factorial
- House Robber
- Mean of an Array
- Cube root of a number
- Shortest un-ordered subarray
- C++ Sets
- Leap Year
- Find the remainder
- Carol Number
- Area of a triangle
- Check perfect square
- Fibonacci to N
- Product Sum
- Strong Numbers
- Sort first half in ascending and second half in descending
- Sum Of Digits
- Ishaan's Sum Problem
- Factorial Number
- Factorial
- Automorphic Number
- Sum of Digit is Palindrome or not
- Greatest of three numbers
- Simple Interest
- Reverse digits
- Power of Pow | Even Number
- Power of Pow | Odd Numbers
- Binary number to decimal number
- Check for three consecutive numbers
- Total digits
- Prime Number
- Adam Number
- Closest Number
- Check squares
- Series AP
- Common Divisors
- Sum of divisors
- Multiples Power
- Angle between hour and minute hand
- Count numbers divisible by M
- Count zero
- Find sum of even factors of a number
- Is digital root of N a prime?
- Sum of first n terms
- Divide the number
- Square Divisors
- Sum of fifth powers of the first n natural numbers
- Find the nth number in the sequence
- Disarium Number
- Min value of x
- Count Squares
- Find X and Y in Linear Equation
- Check if the number is Fibonacci
- Difference between sums of odd and even digits
- Lucky number and a sum
- Anshuman's Favourite Number
- Repeated sum of digits
- Sum of Digit Modified
- Sum of Digits Divisibility
- K-th distinct element
- Product of factors of number
- Narcissistic number
- Print the Kth Digit
- Trimorphic Number
- Swap two numbers
- Unique Numbers
- Decimal to Base K conversion
- Difficult Problems
- Modulus of two double numbers
- Smallest K digit number divisible by X
- Three distinct factors
- Convert from any base to decimal
- Count number of digits after decimal
- Biggest integer having maximum digit sum
- Repetitive Addition Of Digits
- Maximum Handshakes
- Half N by M
- Evaluate the x + a = b statement
- Weird Number
- Perfect Squares in a Range
- The amazing number
- Corner Digits Sum
- Sum of large numbers
- String of Commons
- Perfect Cubes in a Range
- Minimum difference pair
- Finding Position
- Squares in a Matrix
- 2's Complement
- Multiply 2 matrices
- Sum of primes
- Minimum sum of factors
- Squares Difference
- Repeated Sum and then Multiply
- Sorted matrix
- Student record
- Replace by X
- Winner of an election
- Reverse a linked list
- Frequency in a Linked List
- Pairwise swap elements of a linked list
- Node at a given index in linked list
- Linked list of strings forms a palindrome
- Compare two linked lists
- Remove duplicates from an unsorted linked list
- Inorder Traversal
- Reverse a Doubly Linked List
- Bubble Sort
- Selection Sort
- Insertion Sort
- Check for BST
- Right View of Binary Tree
- K distance from root
- Mirror Tree
- Two Mirror Trees
- Maximum Width of Tree
- Delete without head pointer
- Height of Binary Tree
- Balanced Tree Check
- Kth from End of Linked List
- Middle of a Linked List
- Check If Circular Linked List
- Left View of Binary Tree
- Delete Middle of Linked List
- Intersection Sorted Linked Lists
- Find Transition Point
- Queue using two Stacks
- Remove Duplicates from a Sorted Linked List
- Stack using two queues
- Level Order in spiral form
- Reverse Level Order Traversal
- DFS of Graph
- Stack using Linked List
- BFS of graph
- Square Root
- Lowest Common Ancestor in a BST
- Binary Search
- Largest subarray of 0's and 1's
- Remove Duplicates Sorted Array
- Level Order Line by Line
- BST Keys in a Range
- Print all possible strings
- Binary Tree to BST
- Equilibrium index of an array
- Remove every k'th node
- Third largest element
- Convert to Roman No
- Multiply two linked lists
- Josephus problem
- Expression Tree
- Max distance between same elements
- Count Occurrence of digit k
- Delete in a Singly Linked List
- Kth largest element in BST
- Array Duplicates
- Special Stack
- Level order traversal
- Index of an Extra Element
- Sum of given range
- Convert Ternary Expression to Binary Tree
- Intersection of Two Linked Lists
- Split Linked List Alternatingly
- Level of a Node in Binary Tree
- Sum of leaf nodes in BST
- More than n/k Occurrences
- Counting Sort
- Reverse Using Stack
- Full Binary Tree
- Symmetric Tree
- Delete Alternate Nodes
- Merge Lists Alternatingly
- Find the Sum of Last N nodes of the Linked List
- Count Pairs whose sum is equal to X
- Find length of Loop
- Median of BST
- Find n/k th node in Linked list
- Reverse first K of a Queue
- Magical Number
- Sum of Leaf Nodes
- Sum of Right Leaf Nodes
- Sum of Left Leaf Nodes
- C++ STL Priority Queue
- Move all zeros to the front of the linked list
- Delete Mid of a Stack
- Rotate doubly Linked List
- Product of an Array
- C++ Function overloading
- The New Line
- Taking input
- Learn to Comment
- GetLine and Ignore
- Bitwise Operators
- Even Odd
- While loop- printTable
- Learning Macros
- Start Coding - Java
- The New Line - Java
- Data Types - Java
- Learn to Comment - Java
- nextLine and next
- logical Operators - Java
- Bitwise Operators - Java
- Even Odd - Java
- For Loop- primeCheck - Java
- While loop- printTable - Java
- Step by Step Condition - Java
- Swap the array elements
- Matrix Interchange
- Predict the Column
- Delete Array
- Sum of Big Integers
- BigInteger Multiply
- BigInteger mod
- Find the Frequency
- Back to Front
- Pair Sum in Vector
- Get min at pop
- Rightmost different bit
- Longest Consecutive 1's
- Power of 2
- Swap all odd and even bits
- Wave Array
- Frequencies in a Limited Array
- Equilibrium Point
- Array Leaders
- Floor in a Sorted Array
- Minimum Number in a sorted rotated array
- Rotate by 90 degree
- Anagram
- Winner of an election
- String Rotated by 2 Places
- Strings Rotations of Each Other
- The Modified String
- Reverse Words
- Minimum indexed character
- Panagram Checking
- Non Repeating Character
- Parenthesis Checker
- Minimum indexed character
- Generate Binary Numbers
- K largest elements
- Minimum Cost of ropes
- Count number of hops
- First Repeating Element
- Union of Arrays with Duplicates
- Reach a given score
- Check Equal Arrays
- Numbers containing 1, 2 and 3
- Missing in Array
- Product array puzzle
- Roman Number to Integer
- Intersection of Arrays with Distinct
- Excel Sheet | Part - 2
- Adding One
- Max Value Permutation
- Missing And Repeating
- Cumulative frequency of count of each element in an unsorted array
- Minimum element whose N-th power is greater than product of an array
- Buildings receiving sunlight
- Non-Repeating Element
- Last seen array element
- Pairs of equals Sum
- Max value
- Count the elements
- Find Kth Rotation
- Find the closest number
- Pairs which are Divisible by 4
- Adding Ones
- Common in 3 Sorted Arrays
- Sorted and Rotated Minimum
- Maximum no of 1's row
- Sum of elements between k1'th and k2'th smallest elements
- Next greater number set digits
- Search in a Row-Column sorted matrix
- Move All Zeroes to End
- String Duplicates Removal
- Equal Sum and Product
- Find pairs with given relation
- Minimize the sum of product
- Move all negative elements to end
- Strange Sort
- Count the triplets
- Find Pair Given Difference
- Part Sort
- Pairs with difference k
- Finding Number
- Next Greater Even Number
- Bitonic Point
- Left most and right most index
- Single Number
- Alternate Positive Negative
- Check if actual binary representation of a number is palindrome
- Maximum Possible Sum of Products
- Remaining String
- Check if a given string is a rotation of a palindrome
- Remove Consecutive Characters
- Common Subsequence
- Convert a sentence into its equivalent mobile numeric keypad sequence
- Remove b and ac from a given string
- Check if the number is balanced
- Count Alphabets
- Sort in specific order
- Rearrange a string
- Ordering of strings
- Remove Duplicates
- Reverse alternate words
- Nearest multiple of 10
- Add two numbers represented by two arrays
- Reorganize The Array
- Facing the sun
- Greater on right side
- Count Substrings
- Twice Counter
- Word with maximum frequency
- Swap the closest and farthest digits
- Bitonic Generator Sort
- Second Largest
- Convert array into Zig-Zag fashion
- Two Sum - Pair with Given Sum
- Second most repeated string in a sequence
- Check if array contains contiguous integers
- Rearrange to Make arr[i] = i
- Equal point in a string of brackets
- Find all pairs with a given sum
- Number of occurrence
- Maximum repeating number
- The Even Array
- The invariable units digit
- K-Pangrams
- Reversing the equation
- Find the most frequent digit
- Divisibility by 999
- Divisible by 8
- C++ Visible Numbers
- Count even substrings
- Find missing in second array
- First Repeated Character
- Numbers with prime frequencies greater than or equal to k
- Special array reversal
- Even and odd elements at even and odd positions
- String comparison
- Meta Strings
- Min Number of Flips
- Sum of distinct elements for a limited range
- Counts Zeros Xor Pairs
- Substrings with same first and last characters
- Two sum -Pairs with 0 Sum
- Sum of f(a[i], a[j]) over all pairs in an array of n integers
- Positive distinct count
- Large number division
- Play With OR
- Three Great Candidates
- Digits in a set
- At Least K Occurrences
- Element with left side smaller and right side greater
- Common Divisor
- Merging two unsorted arrays in sorted order
- Count the Zeros
- Distinct absolute array elements
- Multiply by 11
- Program for length of the longest word in a sentence
- Maximum value K
- Four Elements
- Palindrome String
- Maximum number of partitions that can be sorted individually to make sorted
- Search array with adjacent diff at most k
- The Optimal Selection
- Sorting all array elements except one
- Delete Array Elements
- K-th missing element
- Pattern Searching
- Count number of words
- Print Bracket Number
- Does robot moves circular
- Divisible by 5 or not
- Divisible by 7
- Is Binary Number Multiple of 3
- Minimum product pair
- Minimum Operations
- Divisibility by 8
- The Buggy Robot
- Check if divisible by 10
- Number of 1 Bits
- Find the Highest number
- Check if a Integer is power of 8 or not
- The Nth Fibonnaci
- Armstrong Numbers
- Compute sum of digits in all numbers from 1 to n
- Maximize XOR
- AND operation
- Three Number Even Sum
- K Smallests in the Original Order
- Lucky Number
- Candy Packets
- Pairs with Positive Negative values
- Remove minimum number of elements
- Reverse Bits
- Semi Prime
- Rearrange the array
- Nth Fibonacci Number
- Ceil The Floor
- Count digits in a factorial
- Number of factors
- Star elements
- Element that appears once where every element occurs twice
- Product of Prime Factors
- Divisor Product
- Maximum Sum Problem
- Count numbers
- GCD and Fibonacci Numbers
- Count Odd Factors
- Make Number Odd
- Sum 1 to n Divisors
- nCr
- Compute (a*b)%c
- Mighty Divisor
- Twisted Prime Number
- Find sum of divisors
- Element in a Sequence
- Sieve of Eratosthenes
- Magic Number
- Count numbers containing 4
- Exponentiation (Set 2)
- Amicable Pair
- Divisible Numbers
- N-divisors
- Greater power
- Happy Number
- Minimum number of Coins
- Number Of Open Doors
- Number of Groups
- Carol Numbers
- Find unit digit in a Product
- Numbers with same first and last digit
- Perfect Numbers
- Pair cube count
- Nth item through sum
- Nth Pentagonal Number
- Nearest Power
- Palindrome numbers
- First K Digits
- Maximum height of the staircase
- Count numbers with unit digit K in given range
- Special Factorial Number
- Smallest number with sum of digits as N and divisible by 10^N
- Magic numbers
- Numbers having alternate bits in range 1 to n
- Factorials Less than or Equal to n
- C++ Exception Handling
- Largest number possible
- Largest sum of digits in all Divisors
- Number that are not divisible
- Carry counter
- Find (a^b)%m
- Count ways to express N as the sum of 1,3 and 4
- Remainder of array multiplication
- Rectangles in N*N Board
- Squares in N*N Chessboard
- Number of divisors in a given range
- Number of Factors of N!
- Primorial of a number
- Compare two fractions
- Division Problem
- Deficient Number
- Trailing zeroes in factorial
- Find smallest values of x and y
- Form a number divisible by 3 using array digits
- Number of ways to find two numbers
- Sum of all prime numbers between 1 and n
- Series GP
- Total number of Strings
- Subtraction and two numbers
- Triangular Number
- Sum of First N Natural Numbers
- Find nth root of m
- Left Most Digit of a product
- Woodall Number
- Greater Palindrome
- Prime Factors
- Circular Prime Number
- Recursive sequence
- Is Square
- Sum of product of all pairs
- Time Difference
- Convert floating point to natural number
- Row with Minimum 1s
- Geek and his Tricky Series
- Squares and divisibility
- Count Primes In Range
- Playing with mobile numbers
- Prime number of set bits
- Type of input
- Sum of Divisors in an array
- Print Pattern
- Primes sum
- Crack the series
- Maximum Sum LCM
- Array to BST
- Count all possible paths from top left to bottom right
- Sum of k smallest elements in BST
- Rank of Matrix
- Sorting Elements of an Array by Frequency
- Rearrange characters
- Find the Maximum sum
- Last two digits of Fibonacci
- Rotate a Linked List
- Sort a linked list of 0s, 1s and 2s
- Add Number Linked Lists
- Rearrange a linked list
- Add 1 to a Linked List Number
- Detect Loop in linked list
- Count BST nodes that lie in a given range
- Merge Sort
- Quick Sort
- Bottom View of Binary Tree
- Intersection in Y Shaped Lists
- Diameter of a Binary Tree
- Merge two sorted linked lists
- Add all greater values to every node in a BST
- Sum Tree
- Tree Boundary Traversal
- LCA in Binary Tree
- Absolute List Sorting
- The Celebrity Problem
- Largest subarray with 0 sum
- Max sum in the configuration
- Get Min from Stack
- Wildcard Pattern Matching
- Linked List to Binary Tree
- Check if subtree
- Remove loop in Linked List
- Largest BST
- Multiply two strings
- Implement Atoi
- Maximum Difference
- Palindrome Linked List
- Closest in BST
- Delete keys in a Linked list
- Merge two BST 's
- Merge k Sorted Arrays
- Find triplets with zero sum
- Sort a stack
- Top View of Binary Tree
- k-th Smallest in BST
- Find Common Nodes in two BSTs
- Merge Sort for Linked List
- Union of Two Linked Lists
- Counting elements in two arrays
- Linked List that is Sorted Alternatingly
- Children Sum in a Binary Tree
- Deletion and Reverse in Circular Linked List
- Convert Level Order Traversal to BST
- ZigZag Tree Traversal
- Count total set bits
- Tower Of Hanoi
- Smallest Positive Missing
- Power Of Numbers
- Rearrange Array Alternately
- Stock buy and sell
- Kadane's Algorithm
- Majority Element
- Count Inversions
- Unique BST's
- Union of 2 Sorted with Duplicates
- Indexes of Subarray Sum
- Count the number of possible triangles
- Triplet Sum in Array
- Boolean Matrix
- Spirally traversing a matrix
- Subarray range with given sum
- Postfix Evaluation
- Next Greater Element
- Infix to Postfix
- Kth smallest element
- Activity Selection
- Minimum Platforms
- Largest number in K swaps
- Combination Sum
- Ways to Reach the n'th Stair
- Egg Dropping Puzzle
- Minimum number of jumps
- Sum of all substrings of a number
- Longest Increasing Subsequence
- Longest Common Subsequence
- 0 - 1 Knapsack Problem
- Lucky Numbers
- Equal Sum Partition
- Sort according to an Array
- Preorder to BST
- Zero Sum Subarrays
- Find whether path exist
- Shortest Common Supersequence
- Most frequent word in an array of strings
- Print Anagrams Together
- Overlapping Intervals
- Word Break
- 4 Sum - All Quadruples
- Excel Sheet | Part - 1
- Sort 0s, 1s and 2s
- Paths to reach origin
- Pascal Triangle
- Maximum Index
- Equal Sum
- Large Factorial
- Sum of Middle elements of two sorted arrays
- Pair array product sum
- Single Among Doubles in a Sorted
- Single Among Doubles
- Pythagorean Triplet
- Mr Modulo and Pairs
- Pair Sum Closest to 0
- Search in Rotated Sorted Array
- Form the Largest Number
- Efficiently sorting numbers in range from 0 to n^2 - 1
- Water Collection
- Add Binary Strings
- Maximum Product Subarray
- Longest subarray with sum divisible by K
- Sort the given array after applying the given equation
- Column name from a given column number
- Palindrome SubStrings
- Form a palindrome
- Nuts and Bolts Problem
- Rotate a Matrix
- Maximum distinct elements after removing K elements
- Count the Reversals
- Combine the strings
- Sum of two large numbers
- Factorials of large numbers
- Reverse each word in a given string
- k largest elements
- Longest Common Substring
- Smallest distinct window
- Longest substring with distinct characters
- Longest Palindrome in a String
- Product Pair
- Integer to Words
- K-th element of two Arrays
- Arranging the array
- Possible groups
- Triplets with Smaller Sum
- Missing element of AP
- First negative in every window of size k
- Not a subset sum
- Minimize the Heights II
- First and Last Occurrences
- Check if any valid sequence is divisible by M
- Nine Divisors
- Valid Substring
- Permutations of a String
- Special Numbers
- Count divisors of product of array elements
- Closest prime number
- Sum of Products
- Subarrays Product Less than K
- Unique Number II
- Bleak Numbers
- Queries for counts of multiples in an array
- Game of XOR
- Largest prime factor
- 3 Divisors
- Maximum Tip Calculator
- Maximize dot product
- Max Sum Increasing Subsequence
- Coin Change (Count Ways)
- Count numbers with given sum
- Coin Change (Minimum Coins)
- Perfect Sum Problem
- Smallest number
- Kth Smallest Factor
- Count ways to N'th Stair(Order does not matter)
- First Digit
- Numbers with 0 as a digit
- nCr
- Maximum path sum in matrix
- Minimum steps to destination
- Maximum GCD Pair
- Part of it.
- Handshakes
- Count distinct pairs with difference k
- Array Pair Sum Divisibility Problem
- Digit multiplier
- Find Last Digit Of a^b for Large Numbers
- N trailing zeroes in factorials
- Prime Pair with Target Sum
- Last non-zero digit in factorial
- Find the last digit when factorial of A divides factorial of B
- Find Prime numbers in a range
- Nth digit in sequence
- Count Divisors of Factorial
- Game with String
- Fraction to Repeating Decimal
- Next Permutation
- Smaller on Left
- How Many X's?
- Rotate Each Row of Matrix K Times
- Stream First Non-repeating
- Segregate even and odd nodes in a Linked List
- Largest square formed in a matrix
- Kth Largest in a Stream
- Two numbers with odd occurrences
- Check Mirror in N-ary tree
- Express as sum of power of natural numbers
- Recursively Remove Adjacent Duplicates
- Linked List Group Reverse
- Reorder List
- Binary Tree to DLL
- Min distance between two given nodes of a Binary Tree
- Max Path Sum 2 Special Nodes
- Trapping Rain Water
- Histogram Max Rectangular Area
- Find median in a stream
- Merge Without Extra Space
- Count Pairs in an Array
- Distinct palindromic substrings
- Count Smaller elements
- Edit Distance
- Minimum sum partition
- Strictly Increasing Array
- Longest valid Parentheses
- N-Queen Problem
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