Question 1

Which one of the following statements is the correct definition for a two-dimensional array of 20 rows and 2 columns of the type integer?

Accepted Answer

A)  int[][] num = new int[20][2]; 
B)  int[][] num = new int[2][20]; 
C)  int[][] num = new int[20,2]; 
D)  int[][] num = new int[2,20]; 
A)  int[][] num = new int[20][2]; 
B)  int[][] num = new int[2][20]; 
C)  int[][] num = new int[20,2]; 
D)  int[][] num = new int[2,20];

Question 2

Which one of the following is the correct definition for initializing data in a two-dimensional array of three rows and two columns?

Accepted Answer

A)  int[][] arr =
{
{ 1, 1, 1 },
{ 2, 2, 2 },
}; 
B)  int[][] arr =
{
{ 1, 1 },
{ 2, 2 },
{ 3, 3 }
}; 
C)  int[][] arr =
{
{ 1, 1 }
{ 2, 2 }
{ 3, 3 }
}; 
D)  int[][] arr =
{
{ 1, 1, 1 }
{ 2, 2, 2 }
{ 3, 3, 3 }
}; 
A)  int[][] arr =
{
{ 1, 1, 1 },
{ 2, 2, 2 },
}; 
B)  int[][] arr =
{
{ 1, 1 },
{ 2, 2 },
{ 3, 3 }
}; 
C)  int[][] arr =
{
{ 1, 1 }
{ 2, 2 }
{ 3, 3 }
}; 
D)  int[][] arr =
{
{ 1, 1, 1 }
{ 2, 2, 2 }
{ 3, 3, 3 }
};

Question 3

Is there any thing wrong with the following code snippet? String[] data = { "abc", "def", "ghi", "jkl" };
String searchedValue = "ghi";
Int pos = 0;
Boolean found = false;
While (pos < data.length)
{
If (data[pos].equals(searchedValue))
{
Found = true;
}
Else
{
Found = false;
}
Pos++;
}
If (found)
{
System.out.println("Found at position: " + pos);
}
Else
{
System.out.println("Not found");
}

Accepted Answer

A)  There is nothing wrong. 
B)  There is compile-time error. 
C)  There is a bounds error. 
D)  There is a logic error. 
A)  There is nothing wrong. 
B)  There is compile-time error. 
C)  There is a bounds error. 
D)  There is a logic error.

Question 4

When an integer literal is added to an array list declared as ArrayList<Integer>, Java performs:

Accepted Answer

A)  casting 
B)  trimming 
C)  auto-boxing 
D)  auto-fixing 
A)  casting 
B)  trimming 
C)  auto-boxing 
D)  auto-fixing

Question 5

What is the valid range of index values for an array of size 10?

Accepted Answer

A)  0 to 10 
B)  1 to 9 
C)  1 to 10 
D)  0 to 9 
A)  0 to 10 
B)  1 to 9 
C)  1 to 10 
D)  0 to 9

Question 6

Which one of the following statements about declaring an array list as a method parameter is true?

Accepted Answer

A)  An array list declared as a method parameter should be accompanied with its size. 
B)  An array list declared as a method parameter is a constant value by default. 
C)  An array list value cannot be modified in a method when the array list is declared as a parameter. 
D)  An array list value can be modified inside the method. 
A)  An array list declared as a method parameter should be accompanied with its size. 
B)  An array list declared as a method parameter is a constant value by default. 
C)  An array list value cannot be modified in a method when the array list is declared as a parameter. 
D)  An array list value can be modified inside the method.

Question 7

What is the output of the following code snippet?
Int[] myarray = { 10, 20, 30, 40, 50 };
System.out.print(myarray[2]);
System.out.print(myarray[3]);

Accepted Answer

A)  1050 
B)  2030 
C)  3040 
D)  4050 
A)  1050 
B)  2030 
C)  3040 
D)  4050

Question 8

Consider the following code snippet: String[] data = { "abc", "def", "ghi", "jkl" };
Using Java 6 or later, which statement grows the data array to twice its size?

Accepted Answer

A)  data = Arrays.copyOf(data, 2 * data.length); 
B)  data = Arrays.copyOf(data, 2); 
C)  data = Arrays.copyOf(data, 2 * data); 
D)  data = Arrays.copyOf(data, 2 * data.size()); 
A)  data = Arrays.copyOf(data, 2 * data.length); 
B)  data = Arrays.copyOf(data, 2); 
C)  data = Arrays.copyOf(data, 2 * data); 
D)  data = Arrays.copyOf(data, 2 * data.size());

Question 9

What will be printed by the statements below?
Int[] values = { 10, 24, 3, 64};
Int position = 0;
For (int i = 1; i  values[position])
Position = i;
System.out.print (position);

Accepted Answer

A) 0 
B) 1 
C) 2 
D) 3 
A) 0 
B) 1 
C) 2 
D) 3

Question 10

Consider the following code snippet:
Int cnt = 0;
Int[][] numarray = new int[2][3];
For (int i = 0; i < 3; i++)
{
For (int j = 0; j < 2; j++)
{
Numarray[j][i] = cnt;
Cnt++;
}
}
What is the value of numarray[1][2] after the code snippet is executed?

Accepted Answer

A)  2 
B)  5 
C)  3 
D)  4 
A)  2 
B)  5 
C)  3 
D)  4

Question 11

What is the result of the following code? for (double element : values)
{
Element = 0;
}

Accepted Answer

A)  The elements of the array values are initialized to zero. 
B)  The elements of the array element are initialized to zero. 
C)  The first element of the array values is initialized to zero. 
D)  The array values is not modified. 
A)  The elements of the array values are initialized to zero. 
B)  The elements of the array element are initialized to zero. 
C)  The first element of the array values is initialized to zero. 
D)  The array values is not modified.

Question 12

Which statements about the enhanced for loop are true for arrays of primitve data?
I. It is suitable for all array algorithms
II. It does not allow the contents of the array to be modified
III. It does not require the use of an index variable

Accepted Answer

A)  I, II 
B)  I, III 
C)  II, III 
D)  I, II, III 
A)  I, II 
B)  I, III 
C)  II, III 
D)  I, II, III

Question 13

What will be printed by the statements below?
Int[] values = { 10, 20, 30, 7};
Int[] numbers = values;
Numbers[2] = 24;
Values[3] = numbers[0] + 6;
System.out.println (numbers[2] + " " + numbers[3] + " "
+ values[2] + " " + values[3]);

Accepted Answer

A) 24 0 30 16 
B) 24 0 30 6 
C) 24 7 30 16 
D) 24 16 24 16 
A) 24 0 30 16 
B) 24 0 30 6 
C) 24 7 30 16 
D) 24 16 24 16

Question 14

What should you check for when calculating the smallest value in an array list?

Accepted Answer

A)  The array list contains at least one element. 
B)  The array list contains at least two elements. 
C)  The array list contains the maximum value in the first element. 
D)  The array list contains the minimum value in the first element. 
A)  The array list contains at least one element. 
B)  The array list contains at least two elements. 
C)  The array list contains the maximum value in the first element. 
D)  The array list contains the minimum value in the first element.

Question 15

The method findLargest should return the largest of any number of double values. For example, the call findLargest (3.4, -2.6, 2.9) should return 3.4 and the call findLargest (9.2, 17.6, 3.4, -2.6, 2.9) should return 17.6. Partial code to do this is given below: double findLargest (double... values)
{
Double max = values[0];
// New code goes here
Return max;
}
What code will complete this method?

Accepted Answer

A)  for (double val: values)
{
If (val > max)
Max = val;
} 
B)  for (int i = 1; i  max)
Max = i;
} 
C)  for (double val: values)
{
If (values[val] > max)
Max = values[val];
} 
D)  for (int i = 1; i  max)
Max = i;
} 
A)  for (double val: values)
{
If (val > max)
Max = val;
} 
B)  for (int i = 1; i  max)
Max = i;
} 
C)  for (double val: values)
{
If (values[val] > max)
Max = values[val];
} 
D)  for (int i = 1; i  max)
Max = i;
}

Question 16

Consider the following code snippet:
Int val = arr[0][2];
Which value of arr is stored in the val variable?

Accepted Answer

A)  The value in the first row and the second column 
B)  The value in the first row and the first column 
C)  The value in the first row and the third column 
D)  The value in the third row and the second column 
A)  The value in the first row and the second column 
B)  The value in the first row and the first column 
C)  The value in the first row and the third column 
D)  The value in the third row and the second column

Question 17

Which one of the following statements is a valid initialization of an array named somearray of ten elements?

Accepted Answer

A)  int[] somearray = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 }; 
B)  int somearray[] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 }; 
C)  int[10] somearray = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 }; 
D)  int somearray[10] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 }; 
A)  int[] somearray = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 }; 
B)  int somearray[] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 }; 
C)  int[10] somearray = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 }; 
D)  int somearray[10] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };

Question 18

When an array myArray is only partially filled, how can the programmer keep track of the current number of elements?

Accepted Answer

A)  access myArray.length() 
B)  maintain a companion variable that stores the current number of elements 
C)  access myArray.currentElements() 
D)  access myArray.length() - 1 
A)  access myArray.length() 
B)  maintain a companion variable that stores the current number of elements 
C)  access myArray.currentElements() 
D)  access myArray.length() - 1

Exam 7: Arrays and Array Lists

Which one of the following statements is the correct definition for a two-dimensional array of 20 rows and 2 columns of the type integer?

Which one of the following is the correct definition for initializing data in a two-dimensional array of three rows and two columns?

When an integer literal is added to an array list declared as ArrayList<Integer>, Java performs:

What is the valid range of index values for an array of size 10?

Which one of the following statements about declaring an array list as a method parameter is true?

What is the output of the following code snippet? Int[] myarray = { 10, 20, 30, 40, 50 }; System.out.print(myarray[2]); System.out.print(myarray[3]);

Consider the following code snippet: String[] data = { "abc", "def", "ghi", "jkl" }; Using Java 6 or later, which statement grows the data array to twice its size?

What will be printed by the statements below? Int[] values = { 10, 24, 3, 64}; Int position = 0; For (int i = 1; i < values.length; i++) If (values[i] > values[position]) Position = i; System.out.print (position);

Consider the following code snippet: Int cnt = 0; Int[][] numarray = new int[2][3]; For (int i = 0; i < 3; i++) { For (int j = 0; j < 2; j++) { Numarray[j][i] = cnt; Cnt++; } } What is the value of numarray[1][2] after the code snippet is executed?

What is the result of the following code? for (double element : values) { Element = 0; }

Which statements about the enhanced for loop are true for arrays of primitve data? I. It is suitable for all array algorithms II. It does not allow the contents of the array to be modified III. It does not require the use of an index variable

What will be printed by the statements below? Int[] values = { 10, 20, 30, 7}; Int[] numbers = values; Numbers[2] = 24; Values[3] = numbers[0] + 6; System.out.println (numbers[2] + " " + numbers[3] + " " + values[2] + " " + values[3]);

What should you check for when calculating the smallest value in an array list?

Consider the following code snippet: Int val = arr[0][2]; Which value of arr is stored in the val variable?

Which one of the following statements is a valid initialization of an array named somearray of ten elements?

When an array myArray is only partially filled, how can the programmer keep track of the current number of elements?

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