*8.18 (Shuffle rows) 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}};
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}};
public class ProgrammingEx8_18 { public static void main(String[] args) { int[][] m = { { 1, 2 }, { 3, 4 }, { 5, 6 }, { 7, 8 }, { 9, 10 } }; shuffle(m); System.out.print("{"); for (int i = 0; i < m.length; i++) { System.out.print("{"); for (int j = 0; j < m[0].length; j++) { System.out.print(m[i][j]); if (j != m[0].length - 1) { System.out.print(","); } else if (i == m.length - 1) { System.out.print("}"); } else { System.out.print("},"); } } } System.out.print("};"); } public static void shuffle(int[][] m) { int row = m.length; int col = m[0].length; int total = row * col; // Go through all the positions in metrix // Select member as random and put it in current position for (int i = 0; i < total; i++) { int sel = intRandom(i, total - 1); // selected member as random int srow = sel / row; int scol = sel % col; // calculate row and column of the current member int crow = i / row; int ccol = i % col; // swap current member with selected member int temp = m[srow][scol]; m[srow][scol] = m[crow][ccol]; m[crow][ccol] = temp; } } public static int intRandom(int lowerBound, int upperBound) { return (int) (lowerBound + Math.random() * (upperBound - lowerBound + 1)); } }
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