ch_7

Which of the following statements are correct?

Assume double[][] x = new double[4][5], what are x.length and x[2].length?

What is the index variable for the element at the first row and first column in array a?

When you create an array using the following statement, the element values are automatically initialized to 0.

int[][] matrix = new int[5][5];

How many elements are array matrix (int[][] matrix = new int[5][5])?

Analyze the following code:

public class Test {
public static void main(String[] args) {
boolean[][] x = new boolean[3][];
x[0] = new boolean[1]; x[1] = new boolean[2];
x[2] = new boolean[3];

System.out.println("x[2][2] is " + x[2][2]);
}
}

Assume int[][] x = {{1, 2}, {3, 4}, {5, 6}}, what are x.length are x[0].length?

Assume int[][] x = {{1, 2}, {3, 4, 5}, {5, 6, 5, 9}}, what are x[0].length, x[1].length, and x[2].length?

What will be displayed by the following program?

public class Test {
public static void main(String[] args) {
int[][] values = {{3, 4, 5, 1}, {33, 6, 1, 2}};

int v = values[0][0];
for (int row = 0; row < values.length; row++)
for (int column = 0; column < values[row].length; column++)
if (v < values[row][column])
v = values[row][column];

System.out.print(v);
}
}

What will be displayed by the following program?

public class Test {
public static void main(String[] args) {
int[][] values = {{3, 4, 5, 1}, {33, 6, 1, 2}};

int v = values[0][0];
for (int[] list : values)
for (int element : list)
if (v > element)
v = element;

System.out.print(v);
}
}

What will be displayed by the following program?

public class Test {
public static void main(String[] args) {
int[][] values = {{3, 4, 5, 1 }, {33, 6, 1, 2}};

for (int row = 0; row < values.length; row++) {
java.util.Arrays.sort(values[row]);
for (int column = 0; column < values[row].length; column++)
System.out.print(values[row][column] + " ");
System.out.println();
}
}
}

What is the output of the following code?

public class Test {
public static void main(String[] args) {
int[][] matrix =
{{1, 2, 3, 4},
{4, 5, 6, 7},
{8, 9, 10, 11},
{12, 13, 14, 15}};

for (int i = 0; i < 4; i++)
System.out.print(matrix[i][1] + " ");
}
}

What is the output of the following code?
public class Test5 {
public static void main(String[] args) {
int[][] matrix =
{{1, 2, 3, 4},
{4, 5, 6, 7},
{8, 9, 10, 11},
{12, 13, 14, 15}};

for (int i = 0; i < 4; i++)
System.out.print(matrix[1][i] + " ");
}
}

Suppose a method p has the following heading:

public static int[][] p()

What return statement may be used in p()?

What will be displayed by the following program?

public class Test {
public static void main(String[] args) {
int[][] values = {{3, 4, 5, 1}, {33, 6, 1, 2}};

for (int row = 0; row < values.length; row++) {
System.out.print(m(values[row]) + " ");
}
}

public static int m(int[] list) {
int v = list[0];
for (int i = 1; i < list.length; i++)
if (v < list[i])
v = list[i];
return v;
}
}

Assume double[][][] x = new double[4][5][6], what are x.length, x[2].length, and x[0][0].length?

What will be displayed by the following code?
public class Test {
public static void main(String[] args) {
int[][][] data = {{{1, 2}, {3, 4}},
{{5, 6}, {7, 8}}};

System.out.print(data[1][0][0]);
}
}

What will be displayed by the following code?
public class Test {
public static void main(String[] args) {
int[][][] data = {{{1, 2}, {3, 4}},
{{5, 6}, {7, 8}}};

System.out.print(ttt(data[0]));
}

public static int ttt(int[][] m) {
int v = m[0][0];

for (int i = 0; i < m.length; i++)
for (int j = 0; j < m[i].length; j++)
if (v < m[i][j])
v = m[i][j];

return v;
}
}