The question is incomplete. The complete question is :
Write a method that shuffles the rows in a two-dimensional int array using the following header: public static void shuffle(int[][] m)
Write a test program that shuffles the following matrix: int[][] m = {{1, 2}, {3, 4}, {5, 6}, {7, 8}, {9, 10}};
Solution :
//filename_suffle.java
#public class shuffle{
public_static_void_main_(String[] args) {
int[][] m = {{1, 2} {3, 4} {5, 6} {7, 8} {9, 10}};
System.out.println("Before shuffle");
displayMatrix(m);
System(dot)out(dot)println("After shuffle");
shuffle(m);
displayMatrix(m);
}
public_static_void_displayMatrix_(int[][] m) {
for (int i = 0; i < m.length; i++) {
for (int j = 0; j < m[i].length; j++) {
System.out.print(m[i][j] + " ");
}
System(dot)out(dot)println("");
}
}
public_static_void_shuffle_(int[][] m) {
int r1; // random row index
for (int i = 0; i < m.length; i++) {
for (int j = 0; j < m[i].length; j++) {
do {
r1 = (int)(Math.random() * m.length);
} while (r1 == i);
int[] temp = m[i];
m[i] = m[r1];
m[r1] = temp;
}
}
}
}