1. In a hospital management system, the Patient class has methods like admit() and discharge(). These methods' signatures are the same in subclasses but have different implementations. What is this an example of?

2. What will the following code output?
java
class Test {
public static void main(String[] args) {
String str = "hello";
str.concat(" world");
System.out.println(str);
}
}

3. In the Stream API, which of these is not a terminal operation?

4. Which method must be implemented when implementing the Runnable interface?

5. What is the size of a pointer in a 64-bit system?

6. What is the output of this program?

#include

template

void print(T x) { std::cout << x; } int main() { print(5);

return 0;

}

7. What is the output of this code?

int a = 5, b = 10;

std::swap(a, b);

std::cout << a << " " << b;

8. In a ticket booking application, multiple users try to book the last available ticket simultaneously. Which Java feature can handle this scenario?

9. What is the purpose of the ForkJoinPool class?

10. What will happen when this code is executed?

#include

class Test {

public:

Test() { std::cout << "Constructor"; } ~Test() { std::cout << "Destructor"; } }; int main() { Test* t = new Test(); return 0; }

11. What does the keyword explicit do in C++?

12. Which of the following functions cannot be used with FILE* in C?

13. Which is true about calloc in C?

14. What is the output of this program?

#include

int main() {

int a = 5, b = 10;

printf("%d %d", a, b);

return 0;

}

15. What does the following code snippet indicate?

void foo() noexcept { }

16. What is the output of the following ?

#include
void main()
{
int a[5] = { 5, 1, 15, 20, 25 };
int i, j, m;
i = ++a[1];
j = a[1]++;
m = a[i++];
printf("%d, %d, %d", i, j, m);
}

17. In a payment gateway system, retrying a failed transaction can cause data corruption if not handled carefully. What technique helps avoid this?

18. Which header file is required for std::thread?

19. What will happen when this code runs?

#include

class A {

public:

A() { std::cout << "Constructor"; } ~A() { std::cout << "Destructor"; } }; int main() { A obj; return 0; }

20. Which function is used to allocate memory in C?