Placement Papers - MCQ Practice Questions

Which design pattern is used when you want to ensure a class has only one instance?

What will be the output? List<Integer> list = new ArrayList<>(); list.add(1); list.add(2); list.add(3); list.remove(1); System.out.println(list);

What is the difference between ArrayList and LinkedList in Java?

Which of the following is NOT a principle of object-oriented programming?

What is the purpose of the 'try-catch' block in Java?

If a HashMap has 1000 entries and the load factor is 0.75, at what capacity will it resize?

What is the time complexity of accessing an element in a balanced Binary Search Tree?

Which protocol is used for secure data transmission over the internet?

What does the SELECT * query do in SQL?

A train travels from City A to City B at 60 km/h and returns from B to A at 40 km/h. If the total journey time is 10 hours, what is the distance between City A and City B?

In a sequence, each term is obtained by adding the previous two terms. If the 1st term is 2 and 2nd term is 3, what is the 6th term?

If PAPER is coded as 16-1-16-5-18, then PENCIL would be coded as?

Four friends A, B, C, and D have different salaries. C earns more than A but less than D. B earns more than D. Who has the highest salary?

What will be the output of the following code snippet? int x = 5; int y = ++x + x++ + x; System.out.println(y);

A can complete a task in 12 days. B can complete the same task in 18 days. If both work together, in how many days will they complete the task?

A train travels from City A to City B at 60 km/h. On the return journey, it travels at 40 km/h. If the total time taken for both journeys is 10 hours, what is the distance between the two cities?

In a sequence, the first term is 2 and each subsequent term is obtained by multiplying the previous term by 3 and subtracting 1. What is the 4th term?

Find the missing number in the series: 4, 9, 25, 49, 121, ?

What will be the output of the following pseudocode? int a = 5, b = 10; while(a < b) { b = b - a; a = a + 1; } print(a, b);

A software developer needs to optimize a SQL query. Currently, the query performs a full table scan on a table with 1 million rows. Which of the following would be the BEST approach to improve performance?