What are the main differences between Java and Python?

Java:

• Statically typed.
• Compiled language, which generally results in faster performance.
• Often used for large-scale enterprise applications.

Python:

• Dynamically typed.
• Interpreted language, which can be slower than compiled languages.
• Often used for web development, data science, and scripting.

How do garbage collection mechanisms work?

Garbage collection is a form of automatic memory management. The garbage collector, or GC, attempts to reclaim garbage, or memory occupied by objects that are no longer in use by the program.

The basic process involves identifying all the objects that are still reachable by the program, and then marking all other objects as garbage. The memory used by the garbage objects is then reclaimed. A common algorithm is Mark and Sweep.

Write a program to reverse a string in C++/Java/Python.

C++:

#include 
#include 
#include 

int main() {
    std::string str = "Hello, World!";
    std::reverse(str.begin(), str.end());
    std::cout << str << std::endl;
    return 0;
}
                

Java:

public class Main {
    public static void main(String[] args) {
        String str = "Hello, World!";
        String reversedStr = new StringBuilder(str).reverse().toString();
        System.out.println(reversedStr);
    }
}
                

Python:

str = "Hello, World!"
reversed_str = str[::-1]
print(reversed_str)
                

How do you implement multithreading in Java and Python?

Java:

You can implement multithreading in Java by extending the `Thread` class or by implementing the `Runnable` interface.

class MyThread extends Thread {
    public void run() {
        System.out.println("Thread is running.");
    }
}

public class Main {
    public static void main(String[] args) {
        MyThread t1 = new MyThread();
        t1.start();
    }
}
                

Python:

You can implement multithreading in Python using the `threading` module.

import threading

def my_func():
    print("Thread is running.")

if __name__ == "__main__":
    t1 = threading.Thread(target=my_func)
    t1.start()
    t1.join()
                

What are templates in C++? Provide an example.

Templates are a feature of C++ that allow functions and classes to operate with generic types. This allows a function or class to work on many different data types without being rewritten for each one.

Example:

template 
T add(T a, T b) {
    return a + b;
}

int main() {
    std::cout << add(2, 3) << std::endl;
    std::cout << add(2.5, 3.5) << std::endl;
    return 0;
}
                

How does Python manage dynamic typing?

Python is a dynamically typed language, which means that the type of a variable is checked at runtime. You don't need to declare the type of a variable when you create it. A variable can hold values of different types at different times.

For example, you can do this in Python:

x = 10
print(type(x))  # 
x = "Hello"
print(type(x))  #