Amazon’s Most Frequently Asked Questions | Set 1

**Level – Easy**

- Get minimum element from stack – Practice here
- Serialize and deserialize a binary tree – Practice here
- Print a binary tree in a vertical order – Practice here
- Celebrity problem – Practice here
- Level order traversal
- Swap the kth element from starting and from the end position – Practice here
- Binary tree to bst – Practice here
- Max sum in the configuration – Practice here
- Find the nth element of spiral matrix – Practice here
- Count the number of occurrences in a sorted array
- Find the smallest window in a string containing all characters of another string
- Find the maximum of all subarrays of size k
- Multiply two numbers represented as a linked list.
- Find the kth smallest element in row wise and column wise sorted matrix
- Minimum swaps required to arrange pairs
- There is an array of N numbers ranging from 1 to N. Only 1 number is missing, return the index of that number
- Find the second largest and second smallest in a given array in single traversal.
- Find power(x,y) without using pow function.(divide and conquer approach required)
- Count possible decoding sequence

**Level – Medium**

- Given two string print them inter leaving strings characters
- Minimum cost required to travel from top left to the bottom right in a matrix
- Maximum difference between node and its ancestors – Practice here
- Min distance between two given nodes of a binary tree – Practice here
- Find the number of island – Practice here
- Topological Sort – Practice here
- Detect cycle in a directed graph – Practice here
- Flattening a link list – Practice here
- Detect a loop in a linked list – Practice here
- Check if a binary tree is BST or not
- Min Cost path
- Count ways to reach nth stair
- Maximum Subarray Problem
- Palindrome Partitioning
- Given a binary tree find the minimum root to leaf height.
- Implement LRU cache

**Level – Hard**

- Boolean paranthesis – Practice here
- Maximum Index – Practice here
- Largest Number formed in the array – Practice here
- Find the length of maximum numbers of consecutive numbers jumped up in an array
- Delete the elements in a linklist whose sum is equal to zero
- Given a list of numbers of odd length design an algorithm to remove a number and divide the rest numbers equaly so as it makes there sum same
- Find diameter of a binary tree

Also see

You may also like to see following Amazon Interview Video.

If you like GeeksforGeeks and would like to contribute, you can also write an article and mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above