SDE - 1

You have been given a square chessboard of size ‘N x N’. The position coordinates of the Knight and the position coordinates of the target are also given.

Your task is to find out the minimum steps a Knight will take to reach the target position.

Example:

knightPosition: {3,4}
targetPosition: {2,1}

The knight can move from position (3,4) to positions (1,3), (2,2) and (4,2). Position (4,2) is selected and the ‘stepCount’ becomes 1. From position (4,2), the knight can directly jump to the position (2,1) which is the target point and ‘stepCount’ becomes 2 which is the final answer. 

Note:

1. The coordinates are 1 indexed. So, the bottom left square is (1,1) and the top right square is (N, N).

2. The knight can make 8 possible moves as given in figure 1.

3. A Knight moves 2 squares in one direction and 1 square in the perpendicular direction (or vice-versa).

You are given a magic grid A with R rows and C columns. In the cells of the grid, you will either get magic juice, which increases your strength by |A[i][j]| points, or poison, which takes away |A[i][j]| strength points. If at any point of the journey, the strength points become less than or equal to zero, then you will die.

You have to start from the top-left corner cell (1,1) and reach at the bottom-right corner cell (R,C). From a cell (i,j), you can only move either one cell down or right i.e., to cell (i+1,j) or cell (i,j+1) and you can not move outside the magic grid. You have to find the minimum number of strength points with which you will be able to reach the destination cell.

You are given some information about the rooms of a military camp. The rooms are numbered from 0 to 'N-1'. Each room contains keys to some other rooms. You can visit a room only if you have a key to that room. Your task is to determine whether each room can be visited or not.

Note:

1. Room 0 is the only room that is initially unlocked and doesn’t require any key to enter.

2. Any other room can be visited only if you have the key to that room.

3. More than one room can have keys to the same room.

4. You are allowed to visit rooms in any order.

5. You can visit any room multiple times.

You are given an integer ‘N’, which denotes there are ‘N’ friends. You are supposed to form some pairs them satisfying the following conditions:

1. Each friend can be paired with some other friend or remain single.

2. Each friend can be a part of at most one pair.

You are supposed to find the total number of ways in which the pairing can be done satisfying both conditions. Since the number of ways can be quite large, you should find the answer modulo 1000000007(10^9+7).

Note:

1. Return the final answer by doing a mod with 10^9 + 7.
2. Pairs {A, B} and {B, A} are considered the same.

Ninja, along with his family, moved to a new city, and Ninja has no friends. He started making new friends from his school. Now he has a number of friends. His friends decided to meet in the evening, but all are confused about where to meet?

Ninja is very busy doing some other works. Can you help Ninja find a place where Ninja and all his friends can meet such that the sum of distance traveled by Ninja and his friends is the minimum possible? Find the place and print the total sum of distances traveled by Ninja and his friends.

You are given the location of Ninja and his friends in the form of a matrix. In the matrix, wherever the value is 1, it means that there is a home at that point (Ninja’s home or the home of some of his friends). Ninja and his friends can meet at any possible coordinate in the matrix, not necessarily at the home of any of the friends.

Manhattan distance is used to calculate the distance between two points, i.e, distance(a, b) = |a.x - b.x| + |a.y - b.y|, (where a.x is the x coordinate of point ‘a’, a.y is the y coordinate of point ‘a’, b.x is the x coordinate of point ‘b’, b.y is the y coordinate of point ‘b’ respectively).

What is the biggest challenge you’ve faced in your current position? 

How would your co-workers describe you? 

What skills would you bring to the job? 

How do you keep up with the latest industry trends?