HackerRank: [Algo] Matrix Rotation

Problem

You are given a 2-D matrix, a, of dimension M x N and a positive integer R. You have to rotate the matrix R times and print the resultant matrix. Rotation should be in anti-clockwise direction.

Rotation of a 4 x 5 matrix is represented by the following figure. Note that in one rotation, you have to shift elements by one step only (refer sample tests for more clarity).

matrix-rotation

It is guaranteed that the minimum of M and N will be even.

Input Format
First line contains three space separated integers, M, N and R, where M is the number of rows, N is number of columns in matrix, and R is the number of times the matrix has to be rotated.
Then M lines follow, where each line contains N space separated positive integers. These M lines represent the matrix.

Output Format
Print the rotated matrix.

Constraints
2 <= M, N <= 300
1 <= R <= 109
min(M, N) % 2 == 0
1 <= aij <= 108, where i[1..M] & j[1..N]

Sample Input #00

4 4 1
1 2 3 4
5 6 7 8
9 10 11 12
13 14 15 16

Sample Output #00

2 3 4 8
1 7 11 12
5 6 10 16
9 13 14 15

Sample Input #01

4 4 2
1 2 3 4
5 6 7 8
9 10 11 12
13 14 15 16

Sample Output #01

3 4 8 12
2 11 10 16
1 7 6 15
5 9 13 14

Sample Input #02

5 4 7
1 2 3 4
7 8 9 10
13 14 15 16
19 20 21 22
25 26 27 28

Sample Output #02

28 27 26 25
22 9 15 19
16 8 21 13
10 14 20 7
4 3 2 1

Sample Input #03

2 2 3
1 1
1 1

Sample Output #03

1 1
1 1

Explanation
Sample Case #00: Here is an illustration of what happens when the matrix is rotated once.

 1  2  3  4      2  3  4  8
 5  6  7  8      1  7 11 12
 9 10 11 12  ->  5  6 10 16
13 14 15 16      9 13 14 15

Sample Case #01: Here is what happens when to the matrix after two rotations.

 1  2  3  4      2  3  4  8      3  4  8 12
 5  6  7  8      1  7 11 12      2 11 10 16
 9 10 11 12  ->  5  6 10 16  ->  1  7  6 15
13 14 15 16      9 13 14 15      5  9 13 14

Sample Case #02: Following are the intermediate states.

1  2  3  4      2  3  4 10    3  4 10 16    4 10 16 22
7  8  9 10      1  9 15 16    2 15 21 22    3 21 20 28
13 14 15 16 ->  7  8 21 22 -> 1  9 20 28 -> 2 15 14 27 ->
19 20 21 22    13 14 20 28    7  8 14 27    1  9  8 26
25 26 27 28    19 25 26 27    13 19 25 26   7 13 19 25



10 16 22 28    16 22 28 27    22 28 27 26    28 27 26 25
 4 20 14 27    10 14  8 26    16  8  9 25    22  9 15 19
 3 21  8 26 ->  4 20  9 25 -> 10 14 15 19 -> 16  8 21 13
 2 15  9 25     3 21 15 19     4 20 21 13    10 14 20  7
 1  7 13 19     2  1  7 13     3  2  1  7     4  3  2  1

Sample Case #03: As all elements are same, any rotation will reflect the same matrix.

Solution

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