Android Puzzles

These Puzzles were created for Google IO Extended 2018.

Transcript

1. IO Extended 2018 PhonePe Puzzles #BlrDroid #BlrKotlin #IO18Extended #PhonePePuzzle
2. Rules for the Quiz 1. Don’t shout the answer. 2. Raise your hand, we will come to you with mic. 3. Who answers first wins. 4. For why questions, answer should be descriptive? Only guessing an option will not be considered as answer. 5. Be a good citizen, one person is eligible to answer only once
3. Which two options holds good for main() method? 1. The method must be public. 2. The method may be any accessibility type except private. 3. The method may be either an instance method or static. 4. The argument list must be declared exactly as String [] args. 5. The argument list may be declared as String… args.
4. Output of the snippet? List<String> names = Arrays.asList("BlrKotlin", "BlrDroid"); names.add("PhonePe"); names.add("Google IO"); Log.d("IOExtended", "Names are - " + names); 1. Prints the names 2. Compilation fails 3. Runtime Exception
5. What it prints? class Main { public static void main(String[] args) { System.out.println("IOExtended!"); // \u000d System.out.println("On 8th May"); } }
6. What’s the output fun main(args: Array<String>) { (1..5).forEach({ i -> if (i > 3) return println(i) }) println("Done") }
7. Android Threading To run a lot of parallel threads, what do you need A. AsyncTask B. Handler Thread C. Thread Pool D. Intent Service
8. Does this print ? println(Unit is Unit) println(null is Any) println(null!! is Nothing)
9. What does this print println(2.5 in 1..3) println(3.5 in 1..3)
10. One more fun main(args: Array<String>) { val whatAmI = {}() println(whatAmI) }
11. Describe a situation where onDestroy() will be called without invoking onPause() and onStop()
12. Minimum Value? System.out.println(Math.min(Integer.MIN_VALUE, 0)); System.out.println(Math.min(Double.MIN_VALUE, 0.0d));
13. What will be the output of following code? public class Test { public static void main(String... x) { int[] arr = new int[9]; for (int i = 0; i < arr.length; i++) { arr[i] = i; } System.out.println(arr[9]); } }
14. Which browser this code opens? class Test { public static void main(String... x) { http://www.google.com System.out.println("Hello World"); } } 1. Chrome 2. Default browser on your machine 3. Compile Time Error 4. Runtime Exception 5. Runs fine
15. What is the output of below code? class Test { public static void main(String... x) { StringBuffer buffer = new StringBuffer('H'); buffer.append('i'); System.out.print(buffer); } } 1. Compile Time Error 2. Prints “Hi” 3. Prints “H” 4. Prints “i”
16. Thank You