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

Rotation of a matrix is represented by the following figure. Note that in one rotation, you have to shift elements by one step only.

matrix-rotation

It is guaranteed that the minimum of m and n will be even.

As an example rotate the Start matrix by 2:

    Start         First           Second
     1 2 3 4       2  3  4  5      3  4  5  6
    12 1 2 5  ->   1  2  3  6 ->   2  3  4  7
    11 4 3 6      12  1  4  7      1  2  1  8
    10 9 8 7      11 10  9  8     12 11 10  9

Function Description

Complete the matrixRotation function in the editor below.

matrixRotation has the following parameter(s):

  • int matrix[m][n]: a 2D array of integers
  • int r: the rotation factor

Prints
It should print the resultant 2D integer array and return nothing. Print each row on a separate line as space-separated integers.

Input Format

The first line contains three space separated integers, , , and , the number of rows and columns in , and the required rotation.
The next lines contain space-separated integers representing the elements of a row of .

Constraints




Sample Input

Sample Input #01

STDIN        Function
-----        --------
4 4 2        rows m = 4, columns n = 4, rotation factor r = 2
1 2 3 4      matrix = [[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12], [13, 14, 15, 16]]
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

Explanation #01

The matrix is rotated through 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 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

Explanation 02

The various states through 7 rotations:

    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 Input #03

2 2 3
1 1
1 1

Sample Output #03

1 1
1 1

Explanation #03

All of the elements are the same, so any rotation will repeat the same matrix.

Limbajul de programare folosit: java8

Cod:

import java.util.Scanner;

public class Solution {
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);

		int M = in.nextInt();
		int N = in.nextInt();
		int R = in.nextInt();
		int[][] matrix = new int[M][N];
		for (int i = 0; i < M; i++) {
			for (int j = 0; j < N; j++) {
				matrix[i][j] = in.nextInt();
			}
		}

		int[][] rotated = new int[M][N];
		for (int i = 0; i * 2 < Math.min(M, N); i++) {
			int height = M - i * 2;
			int width = N - i * 2;
			int circumference = (height + width - 2) * 2;
			int offset = R % circumference;

			Point from = new Point(i, i);
			Point to = new Point(i, i);
			for (int j = 0; j < offset; j++) {
				to = move(to, M, N);
			}

			for (int j = 0; j < circumference; j++) {
				rotated[to.r][to.c] = matrix[from.r][from.c];

				from = move(from, M, N);
				to = move(to, M, N);
			}
		}

		for (int i = 0; i < M; i++) {
			for (int j = 0; j < N; j++) {
				if (j != 0) {
					System.out.print(" ");
				}
				System.out.print(rotated[i][j]);
			}
			System.out.println();
		}

		in.close();
	}

	static Point move(Point p, int M, int N) {
		int circle = Math.min(Math.min(p.r, M - 1 - p.r),
				Math.min(p.c, N - 1 - p.c));
		int height = M - circle * 2;
		int width = N - circle * 2;

		if (p.c == circle && p.r < circle + height - 1) {
			return new Point(p.r + 1, p.c);
		} else if (p.r == M - 1 - circle && p.c < circle + width - 1) {
			return new Point(p.r, p.c + 1);
		} else if (p.c == N - 1 - circle && p.r > circle) {
			return new Point(p.r - 1, p.c);
		} else {
			return new Point(p.r, p.c - 1);
		}
	}
}

class Point {
	int r;
	int c;

	Point(int r, int c) {
		this.r = r;
		this.c = c;
	}
}

Scor obtinut: 1.0

Submission ID: 464602679

Link challenge: https://www.hackerrank.com/challenges/matrix-rotation-algo/problem

Matrix Layer Rotation