SDE - 1

You are given a linked list of 'N' nodes. Your task is to reverse the linked list from position 'X' to 'Y'.

For example:

Assuming, the linked list is 10 -> 20 -> 30 -> 40 -> 50 -> 60 -> NULL. X = 2 and Y = 5. On reversing the given linked list from position 2 to 5, we get 10 -> 50 -> 40 -> 30 -> 20 -> 60 -> NULL.

You have been given a complete binary tree of ‘N’ nodes. The nodes are numbered 1 to ‘N’.

You need to find the ‘next’ node that is immediately right in the level order form for each node in the given tree.

Note :

1. A complete binary tree is a binary tree in which nodes at all levels except the last level have two children and nodes at the last level have 0 children.
2. Node ‘U’ is said to be the next node of ‘V’ if and only if  ‘U’ is just next to ‘V’ in tree representation.
3. Particularly root node and rightmost nodes have ‘next’ node equal to ‘Null’ 
4. Each node of the binary tree has three-pointers, ‘left’, ‘right’, and ‘next’. Here ‘left’ and ‘right’ are the children of node and ‘next’ is one extra pointer that we need to update.

For Example :

The‘next’ node for ‘1’ is ‘Null’, ‘2’ has ‘next’ node ‘6’, ‘5’ has ‘next’ node ‘3’, For the rest of the nodes check below.

A palindrome string is one that reads the same backward as well as forward.

You are given a string 'str'.

Find the minimum number of characters needed to insert in 'str' to make it a palindromic string.

Example :

Input: 'str' = "abca"

Output: 1

Explanation:
If we insert the character ‘b’ after ‘c’, we get the string "abcba", which is a palindromic string. Please note that there are also other ways possible.

There are 4 persons (A, B, C and D) who want to cross a bridge in night.

A takes 1 minute to cross the bridge.
B takes 2 minutes to cross the bridge.
C takes 5 minutes to cross the bridge.
D takes 8 minutes to cross the bridge.
There is only one torch with them and the bridge cannot be crossed without the torch. There cannot be more than two persons on the bridge at any time, and when two people cross the bridge together, they must move at the slower person's pace. Can they all cross the bridge in 15 minutes?

Given an unsorted array of integers, you have to move the array elements in a way such that all the zeroes are transferred to the end, and all the non-zero elements are moved to the front. The non-zero elements must be ordered in their order of appearance.

For example, if the input array is: [0, 1, -2, 3, 4, 0, 5, -27, 9, 0], then the output array must be: [1, -2, 3, 4, 5, -27, 9, 0, 0, 0].

Expected Complexity: Try doing it in O(n) time complexity and O(1) space complexity. Here, ‘n’ is the size of the array.

Bob lives with his wife in a city named Berland. Bob is a good husband, so he goes out with his wife every Friday to ‘Arcade’ mall.

‘Arcade’ is a very famous mall in Berland. It has a very unique transportation method between shops. Since the shops in the mall are laying in a straight line, you can jump on a very advanced trampoline from the shop i, and land in any shop between (i) to (i + Arr[i]), where Arr[i] is a constant given for each shop.

There are N shops in the mall, numbered from 0 to N-1. Bob's wife starts her shopping journey from shop 0 and ends it in shop N-1. As the mall is very crowded on Fridays, unfortunately, Bob gets lost from his wife. So he wants to know, what is the minimum number of trampoline jumps from shop 0 he has to make in order to reach shop N-1 and see his wife again. If it is impossible to reach the last shop, return -1.

You are given a ‘Binary Tree’.

Return the level-order traversal of the Binary Tree.

Example:

Input: Consider the following Binary Tree:

Output: 
Following is the level-order traversal of the given Binary Tree: [1, 2, 3, 5, 6, 4]

9 weights of equal shape and size, 1 has different weight, given a weighing scale, find the min number of ways to find out which weight is the different one