Help with java 2d arrays import javautilRandom public class

Help with java 2d arrays

import java.util.Random;

public class Matrix {
private static final Random rand = new Random(17);

// Create a matrix of size m x n filled with 0s
public static int[][] newMatrix(int m, int n) {
  
  
return new int[m][n];
}

// Create a matrix of size m x n
// that is filled with random numbers from [10,100)
public static int[][] newRandom(int m, int n) {
  
return null; // TODO
}

// Transpose matrix m1 and return the result.
public static int[][] transpose(int[][] matrix) {
  
return null; // TODO
}

// Multiplies matrix with scalar x and returns result
// No input validation is performed
public static int[][] multiply( int x, int[][] matrix ) {
  
return null; // TODO
}

// Adds two matrices and returns the result.
public static int[][] add( int[][] m1, int[][] m2) {
  
return null; // TODO
}
  
public static void printMatrix( int[][] matrix ) {
  
// TODO
// use nested foreach loops to print the matrix
// It should list each row in a separate line
// and all elements separated by a single blank (no brackets)
}

Solution

Matrix.java

import java.util.Random;
public class Matrix {
private static final Random rand = new Random(17);

// Create a matrix of size m x n filled with 0s
public static int[][] newMatrix(int m, int n) {
  
  
return new int[m][n];
}
// Create a matrix of size m x n
// that is filled with random numbers from [10,100)
public static int[][] newRandom(int m, int n) {
int a[][] = new int[m][n];
for(int i=0; i<m; i++){
   for(int j=0;j<n;j++){
       a[i][j] = rand.nextInt(100-10+1)+10;
   }
}
return a; // TODO
}

// Transpose matrix m1 and return the result.
public static int[][] transpose(int[][] matrix) {
   int transpose[][] = new int[matrix.length][matrix[0].length];
     
   for ( int c = 0 ; c < matrix.length ; c++ )
   {
   for ( int d = 0 ; d < matrix[c].length ; d++ )   
   transpose[d][c] = matrix[c][d];
   }
return transpose; // TODO
}

// Multiplies matrix with scalar x and returns result
// No input validation is performed
public static int[][] multiply( int x, int[][] matrix ) {
   for(int i=0; i<matrix.length; i++){
   for(int j=0;j<matrix[i].length;j++){
       matrix[i][j] = matrix[i][j] * x;
   }
}

return matrix; // TODO
}

// Adds two matrices and returns the result.
public static int[][] add( int[][] m1, int[][] m2) {
   int a[][] = new int[m1.length][m1[0].length];
   for(int i=0; i<a.length; i++){
   for(int j=0;j<a[i].length;j++){
       a[i][j] = m1[i][j] + m2[i][j];
   }
}
return a; // TODO
}
  
public static void printMatrix( int[][] matrix ) {
  
// TODO
// use nested foreach loops to print the matrix
// It should list each row in a separate line
// and all elements separated by a single blank (no brackets)
   for(int i=0; i<matrix.length; i++){
       for(int j=0;j<matrix[i].length; j++){
           System.out.print(matrix[i][j]+\" \");
       }
       System.out.println();
   }
}
}