将矩阵向右旋转 K 次

给定一个大小为 N*M 的矩阵和一个数字 K。我们必须将矩阵向右旋转 K 次。
例子：

Input :  N = 3, M = 3, K = 2
         12 23 34
         45 56 67
         78 89 91 

Output : 23 34 12
         56 67 45
         89 91 78 


Input :  N = 2, M = 2, K = 2
         1 2
         3 4
         
Output : 1 2
         3 4

一种简单而有效的方法是将矩阵的每一行视为一个数组并执行数组旋转。这可以通过使用临时数组将元素从 K 复制到数组末尾到数组开头来完成。然后剩下的元素从开始到 K-1 到数组的结尾。
举个例子：

C++

// CPP program to rotate a matrix right by k times
#include 
 
// size of matrix
#define M 3
#define N 3
 
using namespace std;
 
// function to rotate matrix by k times
void rotateMatrix(int matrix[][M], int k) {
  // temporary array of size M
  int temp[M];
 
  // within the size of matrix
  k = k % M;
 
  for (int i = 0; i < N; i++) {
 
    // copy first M-k elements to temporary array
    for (int t = 0; t < M - k; t++)
      temp[t] = matrix[i][t];
 
    // copy the elements from k to end to starting
    for (int j = M - k; j < M; j++)
      matrix[i][j - M + k] = matrix[i][j];
 
    // copy elements from temporary array to end
    for (int j = k; j < M; j++)
      matrix[i][j] = temp[j - k];
  }
}
 
// function to display the matrix
void displayMatrix(int matrix[][M]) {
  for (int i = 0; i < N; i++) {
    for (int j = 0; j < M; j++)
      cout << matrix[i][j] << " ";
    cout << endl;
  }
}
 
// Driver's code
int main() {
  int matrix[N][M] = {{12, 23, 34},
                     {45, 56, 67},
                     {78, 89, 91}};
  int k = 2;
 
  // rotate matrix by k
  rotateMatrix(matrix, k);
 
  // display rotated matrix
  displayMatrix(matrix);
 
  return 0;
}

Java

// Java program to rotate a matrix
// right by k times
 
class GFG
{
    // size of matrix
    static final int M=3;
    static final int N=3;
     
    // function to rotate matrix by k times
    static void rotateMatrix(int matrix[][], int k)
    {
        // temporary array of size M
        int temp[]=new int[M];
         
        // within the size of matrix
        k = k % M;
         
        for (int i = 0; i < N; i++)
        {
         
            // copy first M-k elements
            // to temporary array
            for (int t = 0; t < M - k; t++)
            temp[t] = matrix[i][t];
         
            // copy the elements from k
            // to end to starting
            for (int j = M - k; j < M; j++)
            matrix[i][j - M + k] = matrix[i][j];
         
            // copy elements from
            // temporary array to end
            for (int j = k; j < M; j++)
            matrix[i][j] = temp[j - k];
        }
    }
     
    // function to display the matrix
    static void displayMatrix(int matrix[][])
    {
        for (int i = 0; i < N; i++)
        {
            for (int j = 0; j < M; j++)
            System.out.print(matrix[i][j] + " ");
            System.out.println();
        }
    }
     
    // Driver code
    public static void main (String[] args)
    {
        int matrix[][] = {{12, 23, 34},
                        {45, 56, 67},
                        {78, 89, 91}};
    int k = 2;
     
    // rotate matrix by k
    rotateMatrix(matrix, k);
     
    // display rotated matrix
    displayMatrix(matrix);
    }
}
 
// This code is contributed by Anant Agarwal.

Python3

# Python program to rotate
# a matrix right by k times
 
# size of matrix
M = 3
N = 3
matrix = [[12, 23, 34],
          [45, 56, 67],
          [78, 89, 91]]
 
# function to rotate
# matrix by k times
def rotateMatrix(k) :
 
    global M, N, matrix
     
    # temporary array
    # of size M
    temp = [0] * M
     
    # within the size
    # of matrix
    k = k % M
     
    for i in range(0, N) :
     
        # copy first M-k elements
        # to temporary array
        for t in range(0, M - k) :
            temp[t] = matrix[i][t]
     
        # copy the elements from
        # k to end to starting
        for j in range(M - k, M) :
            matrix[i][j - M + k] = matrix[i][j]
     
        # copy elements from
        # temporary array to end
        for j in range(k, M) :
            matrix[i][j] = temp[j - k]
     
# function to display
# the matrix
def displayMatrix() :
 
    global M, N, matrix
    for i in range(0, N) :
     
        for j in range(0, M) :
            print ("{} " .
                   format(matrix[i][j]), end = "")
        print ()
 
# Driver code
k = 2
 
# rotate matrix by k
rotateMatrix(k)
 
# display rotated matrix
displayMatrix()
 
# This code is contributed by
# Manish Shaw(manishshaw1)

C#

// C# program to rotate a 
// matrix right by k times
using System;
 
class GFG {
     
    // size of matrix
    static int M=3;
    static int N=3;
     
    // function to rotate matrix by k times
    static void rotateMatrix(int [,] matrix,
                             int k)
    {
         
        // temporary array of size M
        int [] temp=new int[M];
         
        // within the size of matrix
        k = k % M;
         
        for (int i = 0; i < N; i++)
        {
         
            // copy first M-k elements
            // to temporary array
            for (int t = 0; t < M - k; t++)
            temp[t] = matrix[i, t];
         
            // copy the elements from k
            // to end to starting
            for (int j = M - k; j < M; j++)
            matrix[i, j - M + k] = matrix[i, j];
         
            // copy elements from
            // temporary array to end
            for (int j = k; j < M; j++)
            matrix[i, j] = temp[j - k];
        }
    }
     
    // function to display the matrix
    static void displayMatrix(int [,] matrix)
    {
        for (int i = 0; i < N; i++)
        {
            for (int j = 0; j < M; j++)
            Console.Write(matrix[i, j] + " ");
            Console.WriteLine();
        }
    }
     
    // Driver code
    public static void Main ()
    {
        int [,] matrix = {{12, 23, 34},
                          {45, 56, 67},
                          {78, 89, 91}};
        int k = 2;
         
        // rotate matrix by k
        rotateMatrix(matrix, k);
         
        // display rotated matrix
        displayMatrix(matrix);
    }
}
 
// This code is contributed by KRV.

Javascript

 
// Javascript program to rotate a matrix
// right by k times   
 
 
// size of matrix
    var M = 3;
     var N = 3;
 
    // function to rotate matrix by k times
    function rotateMatrix(matrix , k)
    {
        // temporary array of size M
        var temp = Array(M).fill(0);
 
        // within the size of matrix
        k = k % M;
 
        for (i = 0; i < N; i++) {
 
            // copy first M-k elements
            // to temporary array
            for (t = 0; t < M - k; t++)
                temp[t] = matrix[i][t];
 
            // copy the elements from k
            // to end to starting
            for (j = M - k; j < M; j++)
                matrix[i][j - M + k] = matrix[i][j];
 
            // copy elements from
            // temporary array to end
            for (j = k; j < M; j++)
                matrix[i][j] = temp[j - k];
        }
    }
 
    // function to display the matrix
    function displayMatrix(matrix) {
        for (i = 0; i < N; i++) {
            for (j = 0; j < M; j++)
                document.write(matrix[i][j] + " ");
            document.write("<br/>");
        }
    }
 
    // Driver code
     
        var matrix = [
        [ 12, 23, 34 ],
        [ 45, 56, 67 ],
        [ 78, 89, 91 ] ];
        var k = 2;
 
        // rotate matrix by k
        rotateMatrix(matrix, k);
 
        // display rotated matrix
        displayMatrix(matrix);
 
// This code contributed by umadevi9616
 

输出：

23 34 12 
56 67 45 
89 91 78