Computer Knowledge

Programming Output Evaluation

1,953 Questions

Programming output evaluation tests the ability to trace code execution in languages like C, Java, and SAS. It focuses on arrays, loops, pointers, and data type conversions. These technical questions are standard in computer knowledge sections for IT officer and bank exams.

Java string bufferC language pointersLoop execution outputsData type conversionsMacro variable evaluation

Programming Output Evaluation Questions

Multiple choice

What will be the output of the following code?

class Apple {
 protected int i = 20;
}
class Banana extends Apple {
 void show() {
  System.out.println(i);
 }
}
class Cat extends Banana {
 void disp() {
  System.out.println(i); //i is also available here 
 }
}
public class Fruit {
 public static void main(String[] args) {
  Cat c = new Cat();
  c.disp();
 }
}

  1. 0

  2. Compile Time Error

  3. 20

  4. 020

  5. 200
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

since i is protected and it will be visible at all its sub classes

Multiple choice

What will be the output of the following statement? g.fillRect(40,40,200,20);

  1. Displays a rectangle of 200X200 pixels starting with top left corner at 40X40 pixels

  2. Displays a rectangle of 40X400 pixels starting with top left corner at 200X200 pixels

  3. Displays a circle of 200X200 pixels starting with top left corner at 40X40 pixels

  4. Displays a circle of 40X40 pixels starting with top left corner at 200X200 pixels

  5. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This statement will draw the rectangle of 200X200 at left corner at 40X40 of the screen.

Multiple choice

The following program is written to create a frame. The program seems to be correct but when it is compiled, the compiler is not accepting it. Why?

class Myframe {
 public static void main(string_args[]) {
  Frame f = new frame("My frame");
  f.setsize(300, 250);
  f.setvisible(true);
 }
}

  1. Frame is not defined properly.

  2. Statement import java.awt.*; is missing.

  3. Statement import java.net.*; is missing.

  4. Statement import java.io.*; is missing.

  5. Set size is not defined properly.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This statement is must, because awt application is used to create the frame. This application is missing.

Multiple choice

What is the output of the given program?

int [] array = {1, 2, 3, 4, 5};

System.arraycopy (array, 2, array, 1, 2);

System.out.print (array [1]);

System.out.print (array[4]);

  1. 34

  2. 35

  3. 24

  4. Run time error

  5. Compilation error
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The two elements 3 and 4 (starting from position with index 2) are copied into position index 1 and 2 in the same array. After the array copy command, the array looks like: {1, 3, 4, 4, 5}.Then, element with index 1 is printed: 3. Then, element with index 4 is printed: 5.

Multiple choice

What is the output of the given program?

StringBuilder sb = new StringBuilder ();

String h1 = HelloWorld;

sb.append(Hello).append (world);

if (h1 == sb.toString())

{

System.out.println(They match);

}

if (h1.equals(sb.toString()))

{

System.out.println(They really match);

}

  1. They Match They Really Match

  2. They really Match

  3. They Match

  4. Blank Output Screen

  5. Compilation fails
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Strings cannot be compared with the usual <, <=, >, or >= operators, and the == and != operators don't compare the characters in the strings.  

Multiple choice

What is the output of the given code?

String message1 = Wham bam!;

String message2 = new String(Wham bam!);

if (message1 == message2)

System.out.println(They match);

if (message1.equals(message2))

System.out.println(They really match);

  1. They matchThey really match

  2. They really match

  3. They match

  4. Nothing will be printed

  5. Compilation fails
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The strings are not the same objects. So, the == comparison fails. As the values of the strings are the same, equals is true. The equals method compares values for equality. == compares references, not values. The use of == with object references is generally limited to the following: Comparing to see if a reference is null. 

Multiple choice

What is the output of the given program code?

public class ScopeTest
{
int z;
public static void main(String[] args)
{
String theString = "Hello World";
System.out.println(theString.charAt(11));
}
}

  1. Blank output screen

  2. StringIndexOutofBound exception

  3. ArrayIndexOutofBound exception

  4. ‘\0’ will be printed

  5. Compilation fails
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

There are only 11 characters in the string hello world. The code theString.charAt(11) retrieves the 12th character, which does not exist. A StringIndexOutOfBoundsException is thrown. Exception in thread main is java.lang. StringIndexOutOfBoundsException. So, this answer is correct.

Multiple choice

How many times is 2 printed as part of output?

public class ScopeTest
{
int z;
public static void main(String[] args){ String[] table = {"aa", "bb", "cc"};
for (String ss: table)
{
int ii = 0;
while (ii < table.length)
{
System.out.println(ss + ", " + ii);
ii++;
}
}
}
}

  1. Zero times

  2. Once

  3. Twice

  4. Thrice

  5. Compilation fails
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The above program produces output: aa, 0aa, 1aa, 2bb, 0bb, 1bb, 2cc, 0cc, 1cc, 2. So, 2 will be printed thrice. Hence, this answer is false.

Multiple choice

What is the output of the given program?

public class arr
{
public static void main(String[] args)
{
int array[] = {0, 1, 2, 3, 4};
int key = 3;
for (int pos = 0;
pos < array.length; ++pos)
{
if (array[pos] == key)
{
break;
}
}
System.out.print("Found " + key + "at " + pos);
}
}

  1. Found 3 at 2

  2. Found 3 at 3

  3. Found 3 at 4

  4. Compilation fails

  5. Run time error
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The following line does not compile: System.out.print (found + key + at + pos). 

Multiple choice

How many times is 0 printed as part of output?

public class ScopeTest
{
int z;
public static void main(String[] args)
{
String[] table = {aa, bb, cc};
for (String ss: table)
{
int ii = 0;
while (ii < table.length)
{
System.out.println(ss + , + ii);
ii++;
}
}
}
}

  1. Zero

  2. Once

  3. Twice

  4. Thrice

  5. Compilation error
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This is the correct choice. The for statement, for (String ss: table) is executed one time for each of the three elements in table.