Kotlin Strings and Ranges

FAQ

Q. What is equals operator?
A. equals operator is used to check if two strings are equal.

Q. What is the use of string interpolation?
A. String interpolation is used to include variables into a string.

Q. What is compareTo operator?
A. It compares two strings on the basis of its ascii value and provides the output according to the difference of ascii values.

Q. What is a range?
A. A range is a mathematical sequence between two terminal points like a range from 1 to 20 will contain all the numbers coming in between.

MCQ

Q. How to get the number of characters in a String str?
a) str.size
b) str.size()
c) str.length
d) str.length()

A. c) str.length

Q. What will be the output for this snippet?
  fun main() {
      val str1 : String = "Hello_World!"
      val str2 : String = str1.subSequence(0, 5)
      println(str2)
  }
  
a) Hello
b) Hell
c) Hello_
d) Compilation Error

A. d) Compilation Error  // because .subSequence returns a character sequence so it will cause type mismatch error as we have defined str2 as a string explicitly

Q. Which of the following is syntactically correct to print the sum of 2 numbers?
a) println("5 + 3 = " 5 + 3)
b) println("5 + 3 = $5+3")
c) println("5 + 3 = {5 + 3}")
d) println("5 + 3 = ${5 + 3}")

A. d) println("5 + 3 = ${5 + 3}")

Q. Which of these are correct range declarations ?
  1) 1..50 || 2) 50..1 || 3) 1 downTo 20 || 4) 20 downTo 1
a) 1 and 3
b) 1 and 4
c) 1 and 2
d) 2 and 3

A. b) 1 and 4