SDE - 1

Bob has been given a triangular pyramid with its vertices marked as ‘O’, ‘X’, ‘Y’ and ‘Z’ and provided with another integer ‘N’. In a single step, Bob can go to any adjacent vertices. Bob will always start from ‘O’ and has to return to ‘O’ after making exactly ‘N’ steps.

Your task is to find out the number of ways he can take to complete his journey.

Note :

As the answer can be very large, return the answer by taking modulo with 1000000007.

For example :

If ‘N’=1 
So in 1 step we can reach either to ‘X’ , ‘Y’ or ‘Z’ and can not travel back to ‘O’.
Thus there are 0 ways.

If ‘N’ =2
So there are total three ways :
(i)  O->X->O
(ii) O->Y->O
(iii) O->Z->O

If ‘N’ = 3
So there are total 6 ways :
(i) O->X->Y->O
(ii) O->X->Z->O
(iii) O->Y->X->O
(iv) O->Y->Z->O
(v) O->Z->X->O
(vi) O->Z->Y->O

You have been given stock values/prices for N number of days. Every i-th day signifies the price of a stock on that day. Your task is to find the maximum profit which you can make by buying and selling the stocks.

 Note :

You may make as many transactions as you want but can not have more than one transaction at a time i.e, if you have the stock, you need to sell it first, and then only you can buy it again.

Given a linked list with a loop and all unique elements. If the loop starts at node X then break the loop from the last node and join it to a node just greater than X. If no such node exists then connect it to null.

For example:

Let the linked list be 1 -> 5 -> 2 -> 4 -> 3 -> 5 and then the last node is connected to node with value 4, which makes a loop. In this linked list, the loop starts from the node with value = 3 and ends at the node with value = 4. 
You are supposed to break the loop ending at 4 and connect it to a node value just greater than 4, which is 5 in this case. So, the final answer is 1 -> 5 -> 2 -> 4 -> 3 and then the last node is connected to node with value 5.

You have been given a sorted array/list 'arr' consisting of ‘n’ elements. You are also given an integer ‘k’.

Now the array is rotated at some pivot point unknown to you.

For example, if 'arr' = [ 1, 3, 5, 7, 8], then after rotating 'arr' at index 3, the array will be 'arr' = [7, 8, 1, 3, 5].

Now, your task is to find the index at which ‘k’ is present in 'arr'.

Note :

1. If ‘k’ is not present in 'arr', then print -1.
2. There are no duplicate elements present in 'arr'. 
3. 'arr' can be rotated only in the right direction.

Example:

Input: 'arr' = [12, 15, 18, 2, 4] , 'k' = 2

Output: 3

Explanation:
If 'arr' = [12, 15, 18, 2, 4] and 'k' = 2, then the position at which 'k' is present in the array is 3 (0-indexed).