Java Developer

You are given a starting position for a rat which is stuck in a maze at an initial point (0, 0) (the maze can be thought of as a 2-dimensional plane). The maze would be given in the form of a square matrix of order 'N' * 'N' where the cells with value 0 represent the maze’s blocked locations while value 1 is the open/available path that the rat can take to reach its destination. The rat's destination is at ('N' - 1, 'N' - 1). Your task is to find all the possible paths that the rat can take to reach from source to destination in the maze. The possible directions that it can take to move in the maze are 'U'(up) i.e. (x, y - 1) , 'D'(down) i.e. (x, y + 1) , 'L' (left) i.e. (x - 1, y), 'R' (right) i.e. (x + 1, y).

Note:

Here, sorted paths mean that the expected output should be in alphabetical order.

For Example:

Given a square matrix of size 4*4 (i.e. here 'N' = 4):
1 0 0 0
1 1 0 0
1 1 0 0
0 1 1 1 
Expected Output:
DDRDRR DRDDRR 
i.e. Path-1: DDRDRR and Path-2: DRDDRR

The rat can reach the destination at (3, 3) from (0, 0) by two paths, i.e. DRDDRR and DDRDRR when printed in sorted order, we get DDRDRR DRDDRR.

You are given a 2D matrix ‘MATRIX’ of ‘N’*’M’ dimension. You have to return the spiral traversal of the matrix.

Example:

Input:
MATRIX = [ [1, 3, 5, 7], [10, 11, 16, 20], [23, 30, 34, 60] ]
Output:
1 3 5 7 20 60 34 30 23 10 11 16

Explanation: Starting from the element in the first row and the first column, traverse from left to right (1 3 5 7), then top to bottom (20 60), then right to left (34 30 23), then bottom to up (10) and then left to right (11 16).

You are given an array ARR having N integers. Your task is to find the sum of Hamming Distance for each pair of the array elements.

Hamming Distance for two given integers 'A' and 'B' is defined as the minimum number of bits that needs to be toggled to make both the integers equal.

For example:

Consider A=4 and B=7
Binary representation of 4 = 100
Binary representation of 7 = 111
For the given example, if we flip the values of the last two least significant bits of A to 1 then A will become 7. As we can change the value of A to B by 2 flips. Therefore the Hamming Distance, in this case, is 2.

How do we measure forty-five minutes using two identical wires, each of which takes an hour to burn? We have matchsticks with us. The wires burn non-uniformly. So, for example, the two halves of wire might burn in 10 minutes and 50 minutes respectively

There is an 8 by 8 chessboard in which two diagonally opposite corners have been cut off. You are given 31 dominos, and a single domino can cover exactly two squares. Can you use the 31 dominos to cover the entire board? 

You are given a string 'STR' containing lowercase English letters from a to z inclusive. Your task is to find all non-empty possible subsequences of 'STR'.

A Subsequence of a string is the one which is generated by deleting 0 or more letters from the string and keeping the rest of the letters in the same order.

Given two non-decreasing sorted arrays, ‘A’ and ‘B’, having ‘N’ and ‘M’ elements, respectively.

You must merge these arrays, ‘A’ and ‘B’, into a sorted array without using extra space. Of all the 'N + M' sorted elements, array 'A' should contain the first 'N' elements, and array 'B' should have the last 'M' elements.

Note:

You must perform the merge operation in place and must not allocate any extra space to merge the two arrays.

For example:

When ‘N’ = 4, ‘A’ = {1, 4, 5, 7} and ‘M’ = 3, ‘B’ = {2, 3, 6}. 
We can merge these two arrays into {1, 2, 3, 4, 5, 6, 7} (The elements of ‘A’ are {1, 2, 3, 4} ).
Hence, the answer is {1, 2, 3, 4, 5, 6, 7}.