# Status Problem Level Completes Likes 141 Separate even and odd integers in a given array Beginner % 0 142 Separate 0’s and 1’s in a given array Beginner % 0 143 Find three elements in an array that sum to a zero. Beginner % 0 144 Find three elements in an array that sum to a given value Beginner % 0 145 Majority Element – Part 1 Beginner % 0 146 Check whether the given number is a perfect square Beginner % 0 147 Check if array is sorted using recursion Beginner % 0 148 Find the Index from which 0 starts Beginner % 0 149 Find the increasing OR decreasing point in an array Beginner % 0 150 Find the only element in array which appears only once Beginner % 1 151 Algorithm to calculate power(k,n). Beginner % 1 152 Find remainder without using modulo operator Beginner % 0 153 Swap two numbers without using extra variable Beginner % 0 154 Number of 1’s in bit representation of a number Beginner % 1 155 Find the right most unset bit OR zero bit of a number Beginner % 1 156 Find the right most set bit of a number Beginner % 1 157 Find the last non repeating character in a given string. Beginner % 0 158 Find the last repeating character in a given string. Beginner % 0 159 Find the first non repeating character in a given string Beginner % 0 160 Find the first repeating character in a given string Beginner % 0 161 Reverse the given Array without using built in function Beginner % 0 162 Implement Stack Using Linked List Beginner % 0 163 Doubly Linked List Complete Implementation Beginner % 0 164 Circular Linked List Complete Implementation Beginner % 0 165 Get the Sum of all left leaves in a Binary tree Beginner % 1 166 Binary Tree-Postorder Traversal - Non Recursive Approach Beginner % 0 167 Binary Tree - Preorder Traversal - Non Recursive Approach Beginner % 0 168 Binary Tree-Inorder Traversal - Non Recursive Approach Beginner % 0 169 Delete the Binary Tree Beginner % 0 170 Search the Element in a binary tree - With and Without Recursion Beginner % 0 171 Tree Traversals Beginner % 1 172 Find the Size of a Binary Tree without Recursion Beginner % 0 173 Find the Kth Smallest/Largest Element in an Array Beginner % 0 174 Priority Queue in Data Structure Beginner % 0 175 Find the Second Largest Element in an Array Beginner % 1 Separate even and odd integers in a given array Separate 0’s and 1’s in a given array Find three elements in an array that sum to a zero. Find three elements in an array that sum to a given value Majority Element – Part 1 Check whether the given number is a perfect square Check if array is sorted using recursion Find the Index from which 0 starts Find the increasing OR decreasing point in an array Find the only element in array which appears only once Algorithm to calculate power(k,n). Find remainder without using modulo operator Swap two numbers without using extra variable Number of 1’s in bit representation of a number Find the right most unset bit OR zero bit of a number Find the right most set bit of a number Find the last non repeating character in a given string. Find the last repeating character in a given string. Find the first non repeating character in a given string Find the first repeating character in a given string Reverse the given Array without using built in function Implement Stack Using Linked List Doubly Linked List Complete Implementation Circular Linked List Complete Implementation Get the Sum of all left leaves in a Binary tree Binary Tree-Postorder Traversal - Non Recursive Approach Binary Tree - Preorder Traversal - Non Recursive Approach Binary Tree-Inorder Traversal - Non Recursive Approach Delete the Binary Tree Search the Element in a binary tree - With and Without Recursion Tree Traversals Find the Size of a Binary Tree without Recursion Find the Kth Smallest/Largest Element in an Array Priority Queue in Data Structure Find the Second Largest Element in an Array 1 2 3 4 5 6 7