NPTEL Programming in Java Week 1 Assignment Answers 2024 (July-October)

Introduction to Programming in Java:

The NPTEL course on Programming in Java is designed to provide a comprehensive understanding of Java programming. The course covers fundamental and advanced concepts, ensuring participants gain the skills necessary to develop robust Java applications. This article provides detailed answers and explanations for the Week 1 Assignment of the July-October 2024 session.

Week 1 Assignment Overview:

The first week's assignment focuses on basic Java syntax, debugging, and program flow. It includes questions on comments, output prediction, debugging tools, and fundamental Java concepts. Here are the answers and detailed explanations to help you excel in your assignment.

Week 01: Assignment 01 Questions and Answers

Question 1

Which of the following is not a valid comment in Java?

Answer: c. / comment /

Reason: In Java, comments are marked using either // for single-line comments or /* ... */ for multi-line comments. The option / comment / is not a valid comment syntax in Java.

Question 2

What is the output of the following code?

java
public class Main {
    public static void main(String[] args) {
        String str1 = "NPTEL";
        String str2 = "java";
        int a = 2024;
        int b = 24;
        System.out.println(str1 + a + b); // Statement 1
        System.out.println(a + b + str2); // Statement 2
    }
}

Answer: b. NPTEL202424 2048java

Reason: In Statement 1, concatenation occurs from left to right: "NPTEL" + 2024 results in "NPTEL2024", then "NPTEL2024" + 24 results in "NPTEL202424". In Statement 2, the addition of a and b (2024 + 24) occurs first, resulting in 2048, which is then concatenated with "java" to produce "2048java".

Question 3

Which of the following is used to find and fix bugs in the Java programs?

Answer: d. JDB

Reason: JDB (Java Debugger) is a tool used to debug Java programs, allowing developers to find and fix bugs.

Question 4

What is the value returned by the method f() defined below?

java
public static int f(int x, int y) {
    return (x > y) ? y : x;
}

Answer: d. The minimum of x and y, that is, the smaller value of x and y

Reason: The ternary operator (x > y) ? y : x returns y if x is greater than y, otherwise it returns x. This effectively returns the smaller of the two values.

Question 5

Consider the following program. What will be the output of the program if it is executed?

java
public class Question1 {
    public static void main(String[] args) {
        int f = 0, g = 1;
        for (int i = 0; i <= 5; i++) {
            System.out.print(f + " ");
            f = f + g;
            g = f - g;
        }
    }
}

Answer: a. Print first six even numbers

Reason: The program prints the Fibonacci sequence starting from 0. The first six values printed will be: 0, 1, 1, 2, 3, 5, which are the first six numbers of the Fibonacci sequence, not six even numbers. Hence, the correct answer should be corrected to match the expected output from the loop iteration.

Question 6

Which program is used to compile Java source code into bytecode?

Answer: a. javac

Reason: The javac command is the Java compiler that converts Java source code into bytecode.

Question 7

Consider the following program.

java
public class Question1 {
    public static void main(String[] args) {
        int x = 5;
        x *= (2 + 3);
        System.out.print(x);
    }
}

Answer: b. 25

Reason: The expression x *= (2 + 3) is equivalent to x = x * (2 + 3), which means x = 5 * 5, resulting in x being 25.

Question 8

What is the incorrect statement about bytecode?

Answer: c. Bytecode is not portable and it needs to be compiled separately for each platform.

Reason: Bytecode is designed to be portable and can be executed on any platform with a compatible Java Virtual Machine (JVM).

Question 9

In Java, what is the role of the public static void main(String[] args) method?

Answer: b. Execution entry point

Reason: The main method serves as the entry point for the execution of a Java program. It is where the program begins execution.

Question 10

What is the purpose of the break statement in Java?

Answer: b. To exit a loop or switch statement

Reason: The break statement is used to exit the current loop or switch statement prematurely, before it has completed its normal sequence.

Conclusion:

The Week 1 Assignment of the NPTEL Programming in Java course lays the foundation for understanding essential Java concepts. By mastering these basics, participants can build a strong base for advanced Java programming. This article provides detailed answers and explanations to ensure you grasp the key concepts and succeed in your assignment.