SDE - 1

You are given a Singly Linked List of integers. Return true if it has a cycle, else return false.

A cycle occurs when a node's next points back to a previous node in the list.

Example:

In the given linked list, there is a cycle, hence we return true.

You have been given a number of stairs. Initially, you are at the 0th stair, and you need to reach the Nth stair.

Each time, you can climb either one step or two steps.

You are supposed to return the number of distinct ways you can climb from the 0th step to the Nth step.

Note:

Note: Since the number of ways can be very large, return the answer modulo 1000000007.

Example :

N=3

We can climb one step at a time i.e. {(0, 1) ,(1, 2),(2,3)} or we can climb the first two-step and then one step i.e. {(0,2),(1, 3)} or we can climb first one step and then two step i.e. {(0,1), (1,3)}.

Create a function that determines whether a given number N belongs to the Fibonacci sequence. If N is found in the Fibonacci sequence, the function should return true; otherwise, it should return false.

You have been given a curve whose edges are parallel to either x-axis or y-axis. You need to return another curve which will pass through the midpoints of all the edges of the curve. The curve will be given in the form of a linked list, where each node represents the coordinates of the curve.

The curve to be returned will also be in the form of a linked list, where each node may represent the coordinates of the midpoints of the edges.

Note

1. The coordinates of the curve will be given in non-descending order of x coordinate from start to end of the linked list and for every two adjacent coordinates either the x-coordinate or the y-coordinate will be the same.
2. All the coordinates will be pairwise distinct i.e there are no two coordinates (x1, y1) and (x2, y2) such that x1 = x2 and y1 = y2.
3. The first coordinate and the last coordinate in the input can be assumed as the starting point and the ending point of the curve respectively.
4. You may assume that the starting point and ending point of the curve will be the midpoint of the first edge, and the last edge of the input curve( in the order of input coordinates) respectively.
5. If the coordinates of the midpoint are not whole numbers, you may take the floor value of the coordinates. For example, the midpoint (3.5, 5) will be taken as (3, 5).