prerna saini
prerna saini
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  1. Change/add only one character and print '*' exactly 20 times
  2. Median of two sorted arrays of same size
  3. Block swap algorithm for array rotation
  4. Queue using Stacks
  5. Identical Linked Lists
  6. Print all sequences of given length
  7. K'th smallest element in BST using O(1) Extra Space
  8. To find sum of two numbers without using any operator
  9. Generate integer from 1 to 7 with equal probability
  10. Sort a nearly sorted (or K sorted) array
  11. Implement Stack using Queues
  12. Generate n-bit Gray Codes
  13. A Pancake Sorting Problem
  14. Remove "b" and "ac" from a given string
  15. Stable Marriage Problem
  16. Print Common Nodes in Two Binary Search Trees
  17. Print cousins of a given node in Binary Tree
  18. Clone a linked list with next and random pointer in O(1) space
  19. Iterative function to check if two trees are identical
  20. Rearrange a linked list such that all even and odd positioned nodes are together
  21. Rearrange a Linked List in Zig-Zag fashion
  22. Add 1 to a number represented as linked list
  23. Point arbit pointer to greatest value right side node in a linked list
  24. Sort linked list which is already sorted on absolute values
  25. Delete middle of linked list
  26. Maximum Consecutive Increasing Path Length in Binary Tree
  27. Binary Indexed Tree : Range Updates and Point Queries
  28. Print all nodes in a binary tree having K leaves
  29. Partitioning a linked list around a given value and keeping the original order
  30. Depth of the deepest odd level node in Binary Tree
  31. Check linked list with a loop is palindrome or not
  32. Length of longest palindrome list in a linked list using O(1) extra space
  33. Sum of nodes at k-th level in a tree represented as string
  34. Count half nodes in a Binary tree (Iterative and Recursive)
  35. Binary Search Tree insert with Parent Pointer
  36. Find first non matching leaves in two binary trees
  37. Change a Binary Tree so that every node stores sum of all nodes in left subtree
  38. How to implement decrease key or change key in Binary Search Tree?
  39. Convert left-right representation of a binary tree to down-right
  40. Number of subtrees having odd count of even numbers
  41. Level with maximum number of nodes
  42. Find distance from root to given node in a binary tree
  43. Count full nodes in a Binary tree (Iterative and Recursive)
  44. k-th distinct (or non-repeating) element in an array.
  45. Partitioning a linked list around a given value and If we don't care about making the elements of the list "stable"
  46. Delete leaf nodes with value as x
  47. Averages of Levels in Binary Tree
  48. Convert a given Binary tree to a tree that holds Logical AND property
  49. Check whether a given binary tree is perfect or not
  50. Check whether the length of given linked list is Even or Odd
  51. Iterative method to check if two trees are mirror of each other
  52. Find median of BST in O(n) time and O(1) space
  53. Leaf nodes from Preorder of a Binary Search Tree
  54. Find mirror of a given node in Binary tree
  55. Arrange consonants and vowels nodes in a linked list
  56. Print all internal nodes of a Binary tree
  57. Largest number in BST which is less than or equal to N
  58. Squareroot(n)-th node in a Linked List
  59. String which when repeated exactly K times gives a permutation of S
  60. Iterative method to find ancestors of a given binary tree
  61. Reverse a Linked List in groups of given size | Set 2
  62. Tracking current Maximum Element in a Stack
  63. Next greater element in same order as input
  64. Remove brackets from an algebraic string containing + and - operators
  65. Shortest distance between two nodes in BST
  66. Merge two sorted lists (in-place)
  67. Insert node into the middle of the linked list
  68. Check if stack elements are pairwise consecutive
  69. Diameter of a Binary Tree in O(n) [A new method]
  70. Print the nodes at odd levels of a tree
  71. Remove all leaf nodes from the binary search tree
  72. Check if the string contains consecutive letters and each letter occurs exactly once
  73. Insert a node after the n-th node from the end
  74. K-th ancestor of a node in Binary Tree
  75. Check if given Preorder, Inorder and Postorder traversals are of same tree
  76. Find smallest and largest elements in singly linked list
  77. Count numbers in range such that digits in it and it's product with q are unequal
  78. Replace node with depth in a binary tree
  79. Pairs of Positive Negative values in an array
  80. Length of longest strict bitonic subsequence
  81. Check whether a binary tree is a full binary tree or not | Iterative Approach
  82. Possible edges of a tree for given diameter, height and vertices
  83. Find next right node of a given key | Set 2
  84. Count Non-Leaf nodes in a Binary Tree
  85. Height of binary tree considering even level leaves only
  86. Tilt of Binary Tree
  87. Largest value in each level of Binary Tree | Set-2 (Iterative Approach)
  88. Modify a binary tree to get preorder traversal using right pointers only
  89. Sum of heights of all individual nodes in a binary tree
  90. Rank of an element in a stream
  91. Rotate Doubly linked list by N nodes
  92. Check if two strings are permutation of each other
  93. Get maximum left node in binary tree
  94. Check if linked list is sorted (Iterative and Recursive)
  95. K'th Largest element in BST using constant extra space
  96. Print BST keys in given Range | O(1) Space
  97. Preorder predecessor of a Node in Binary Tree
  98. Postorder successor of a Node in Binary Tree
  99. Check if a binary tree is sorted level-wise or not
  100. Floor in Binary Search Tree (BST)
  101. Minimum length of the shortest path of a triangle
  102. Length of largest sub-array having primes strictly greater than non-primes
  103. Print all even nodes of Binary Search Tree
  104. Find number of Positional Elements
  105. String after processing backspace characters
  106. Round to next greater multiple of 8
  107. Find number of cavities in a matrix
  108. Immediate smallest number after re-arranging the digits of a given number
  109. Minimum Increment / decrement to make array elements equal
  110. Count pairs from two arrays having sum equal to K
  111. Find the player who rearranges the characters to get a palindrome string first
  112. Count pairs (A, B) such that A has X and B has Y number of set bits and A+B = C
  113. Number of moves required to guess a permutation.
  114. Level Order Predecessor of a node in Binary Tree
  115. Level Order Successor of a node in Binary Tree
  116. Find Bit whose minimum sequence flips makes all bits same
  117. Print all odd nodes of Binary Search Tree
  118. Determine the count of Leaf nodes in an N-ary tree
  119. Print the last k nodes of the linked list in reverse order | Recursive approach
  120. Sum of nodes at maximum depth of a Binary Tree | Set 2
  121. Make palindromic string non-palindromic by rearranging its letters
  122. Minimum spanning tree cost of given Graphs
  123. Distribute candies in a Binary Tree
  124. Pairwise swap adjacent nodes of a linked list by changing pointers | Set 2
  125. Maximum length subsequence such that adjacent elements in the subsequence have a common factor
  126. Program to reverse a linked list using Stack
  127. Reverse zigzag Traversal of a Binary Tree
  128. Check if a string can be converted to another string by replacing vowels and consonants
  129. Count primes that can be expressed as sum of two consecutive primes and 1
  130. Print Stack Elements from Bottom to Top
  131. Zig-Zag traversal of a Binary Tree using Recursion
  132. Minimum removals to make array sum odd
  133. Maximum Bitwise AND pair from given range
  134. Number of trailing zeroes in base 16 representation of N!
  135. Count paths with distance equal to Manhattan distance
  136. Find the number of solutions to the given equation
  137. Find whether only two parallel lines contain all coordinates points or not
  138. Sum of the natural numbers (up to N) whose modulo with K yield R
  139. XOR of a submatrix queries
  140. Anti Clockwise spiral traversal of a binary tree
  141. Sum of minimum element of all sub-sequences of a sorted array
  142. Sum of minimum element of all subarrays of a sorted array
  143. Ways to Remove Edges from a Complete Graph to make Odd Edges
  144. Find last five digits of a given five digit number raised to power five
  145. Maximum average of a subarray of size of atleast X and atmost Y
  146. Find A and B from list of divisors
  147. Clockwise Spiral Traversal of Binary Tree | Set - 2
  148. Print leaf nodes in binary tree from left to right using one stack
  149. Program to check if an Array is Palindrome or not
  150. Reverse Anti Clockwise Spiral Traversal of a Binary Tree
  151. Count of numbers from range [L, R] whose sum of digits is Y
  152. Number of steps required to reach point (x,y) from (0,0) using zig-zag way
  153. Smallest and Largest Palindrome with N Digits
  154. Number of pairs from the first N natural numbers whose sum is divisible by K
  155. Print the longest prefix of the given string which is also the suffix of the same string
  156. Minimum cost to reach end of array array when a maximum jump of K index is allowed
  157. Program to find the kth character after decrypting a string
  158. Program to find the time after K minutes from given time
  159. Minimum number of given operation required to convert n to m
  160. Number of ways in which the substring in range [L, R] can be formed using characters out of the range
  161. Count of sub-arrays whose elements can be re-arranged to form palindromes
  162. Maximum consecutive one’s (or zeros) in a binary circular array
  163. Minimum value to add to arr[i] so that an array can be split at index i with equal sum
  164. Number of ways to go from one point to another in a grid
  165. Reverse alternate levels of a perfect binary tree using Stack
  166. Find sum of even and odd nodes in a linked list
  167. Check whether factorial of N is divisible by sum of first N natural numbers
  168. Check if factorial of N is divisible by the sum of squares of first N natural numbers
  169. Element in a matrix starting from which anti-clockwise traversal ends at the last element
  170. Increment odd positioned elements by 1 and decrement even positioned elements by 1 in an Array
  171. Check whether the sum of element of a node is equal to the given key value
  172. Elements greater than the previous and next element in an Array