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