Problems # Status Problem Level Completes Likes 386 Backtracking - N Queens Problem - Better Solution Hard % 0 387 Backtracking - N Queens Problem Hard % 0 388 Find the Kth Smallest/Largest Element in an Array Beginner % 0 389 Priority Queue in Data Structure Beginner % 0 390 Find the Second Largest Element in an Array Beginner % 0 391 Breadth-First Search/Traversal in a Graph. Hard % 0 392 Breadth-First Search/Traversal in a Binary Tree Beginner % 0 393 Sort Names by their Last Names. Beginner % 0 394 Backtracking - Rat In A Maze Puzzle Hard % 0 395 Backtracking - SUDOKU Solver Hard % 0 396 Introduction To Backtracking Programming Beginner % 0 397 Dynamic Programming - Stairs Climbing Puzzle Beginner % 0 398 Dynamic Programming - Minimum Coin Change Problem Medium % 0 399 Introduction To Dynamic Programming - Fibonacci Series Beginner % 0 400 Merge K Sorted Arrays Hard % 0 401 Find the Deepest Left Node in a Binary Tree. Medium % 0 402 Find a Number occurring odd number of times in a Given array Beginner % 0 403 Rearrange the Array of Given Range N, such that A[i]=i Medium % 1 404 Find a Missing Number From a Sequence of Consecutive Numbers | XOR Method Beginner % 0 405 Find the Max element in a Given Binary Tree Beginner % 0 406 Populate Next Siblings Pointers in a Given Binary Tree OR Populate Next Right Pointers in Each Node Hard % 0 407 Check If One Binary is Mirror Tree of another Binary Tree. Beginner % 0 408 Print All Paths From Root In a Binary Tree Whose Sum is Equal to a Given Number Medium % 0 409 Diameter Of a Binary Tree Hard % 1 410 Do the Reverse Level Order Traversal in a binary tree Medium % 0 411 Find the Deepest Node in a Binary Tree. Medium % 0 412 Find the Height of a tree without using Recursion Medium % 0 413 Print All The Full Nodes in a Binary Tree Beginner % 0 414 Binary Min-Max Heap Implementation Hard % 0 415 Magic Index - Find Index In Sorted Array Such That A[i] = i. Beginner % 0 416 Find numbers that are palindrome in the decimal and octal Representations Beginner % 0 417 Find All the Well Ordered Permutations of a Given String. Medium % 0 418 Find the Increasing Triplet Sub-sequence in an array Medium % 0 419 Construct a Special Triangle from a Given Array Beginner % 0 420 Colorful Numbers Hard % 0 Backtracking - N Queens Problem - Better Solution Backtracking - N Queens Problem 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 Graph. Breadth-First Search/Traversal in a Binary Tree Sort Names by their Last Names. Backtracking - Rat In A Maze Puzzle Backtracking - SUDOKU Solver Introduction To Backtracking Programming Dynamic Programming - Stairs Climbing Puzzle Dynamic Programming - Minimum Coin Change Problem Introduction To Dynamic Programming - Fibonacci Series Merge K Sorted Arrays Find the Deepest Left Node in a Binary Tree. Find a Number occurring odd number of times in a Given array Rearrange the Array of Given Range N, such that A[i]=i Find a Missing Number From a Sequence of Consecutive Numbers | XOR Method Find the Max element in a Given Binary Tree Populate Next Siblings Pointers in a Given Binary Tree OR Populate Next Right Pointers in Each Node Check If One Binary is Mirror Tree of another Binary Tree. Print All Paths From Root In a Binary Tree Whose Sum is Equal to a Given Number Diameter Of a Binary Tree Do the Reverse Level Order Traversal in a binary tree Find the Deepest Node in a Binary Tree. Find the Height of a tree without using Recursion Print All The Full Nodes in a Binary Tree Binary Min-Max Heap Implementation Magic Index - Find Index In Sorted Array Such That A[i] = i. Find numbers that are palindrome in the decimal and octal Representations Find All the Well Ordered Permutations of a Given String. Find the Increasing Triplet Sub-sequence in an array Construct a Special Triangle from a Given Array Colorful Numbers 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16