1.	Sample Program
fun main() 
{
    println("Hello, world!!!")
}
2.main() function with parameters
fun main(args : Array<String>) {
println("Hello World")
}
3. val / var demonstration
fun main()
{
var name = "Kotlin"          // String (text)
val birthyear = 2023         // Int (number)

println(name)          // Print the value of name
println(birthyear)     // Print the value of birthyear

}
OR
// val / var demonstration
fun main()
{
var name: String = "KOTLIN CSE B" // String
val birthyear: Int = 2023 // Int

println(name)
println(birthyear)

}
OR
// val / var demonstration
fun main()
{
var name: String 
    name= "KOTLIN CSE B" // String
val birthyear: Int = 2023 // Int
println(name)
println(birthyear)
}
//  var demonstration
fun main()
{
var name= "CSE B"
 name = "CVR"  //  can be reassigned
println(name)   
}


//  val demonstration
fun main()
{
val name= "CSE B"
 name = "CVR"  //  cannot be reassigned
println(name)   
}

4.DATA TYPE demonstration
fun main()
{
val a: Int = 5                // Int
val b: Double = 5.99        // Double
val c: Char = 'v'          // Char
val d: Boolean = true     // Boolean
val e: String = "CSE B"      // String
val f: Float = 100.00f      // float
println("a value is:" +a)
println("b value is:" +b)
println("c value is:" +c)
println("d value is:" +d)
println("e value is:" +e) 
println("f value is:" +f)
}
5.escape sequences of character demonstration
fun main()
{
println('\n') //prints a newline character
println('\t') //prints a  tab character
println('\b') //prints a backspace character
println('\r') //prints a form feed character
println('\'') //prints a single quote character
println('\"') //prints a double quote character
println('\$') //prints a dollar $ character
println('\\') //prints a back slash \ character
}
6.ARRAY  demonstration
fun main()
{
  val  n:IntArray = intArrayOf(1, 2, 3, 4, 5)
 println("Value at 3rd position : " + n[2])
}
7.TYPE CONVERSION demonstration
fun main()
{
    val x: Int = 100
   val y: Long = x.toLong()
   println(y)
}
8.ARTHIMETIC OPERATOR demonstration
fun main()
{
    var sum1 = 100 + 50       // 150 (100 + 50)
var sum2 = sum1 + 250     // 400 (150 + 250)
var sum3 = sum2 + sum2    // 800 (400 + 400)
println(sum3)
}
9.ASSIGNMENT OPERATOR demonstration
fun main()
{
    var sum1 = 100       // ASSIGN A VALUE
    println(sum1)
}
10.COMPARISION  OPERATOR demonstration
fun main() {  
  var x = 5
 var y = 3
  println(x > y) // returns true because 5 is greater than 3
}
11.logical  OPERATOR demonstration
fun main() {  
    var x = 5
  println(x > 3 && x < 10) // returns true because 5 is greater than 3 AND 5 is less than 10

}
12.STRING demonstration
fun main() {  
    var a:String="CSE B"
  println(a[2]) // DISPLAYS CHARACTER AT LOACTION OR INDEX 2

}
13.IF ELSE demonstration
fun main() {  
  val x = 20
val y = 18
if (x > y) {
  println( "x is greater than y" )
}
else {
        println( "x is lesser than y" ) 
    } }
14.WHEN demonstration
fun main() {  
  val day = 4
  val result = when (day) {
  1 -> "Monday"
  2 -> "Tuesday"
  3 -> "Wednesday"
  4 -> "Thursday"
  5 -> "Friday"
  6 -> "Saturday"
  7 -> "Sunday"
  else -> "Invalid day."
}
println(result)         // DISPLAYS OUTPUT AS "Thursday"
}
15.WHILE Loop demonstration
fun main() {  
  var i = 0
while (i < 5) {
  println(i)
  i++
} 
}
16.DO WHILE LOOP  demonstration
fun main() { 
    var i=0
 do {
  println(i)
  i++
  }
while (i < 5) 
}
17.FOR  LOOP  demonstration
fun main() { 
    val cse = arrayOf("CSE A", "CSE B", "CSE C", "CSE D")
for (x in cse) {
  println(x)
} 
}
18.BREAK  demonstration
fun main() { 
   var i = 0
while (i < 10) {
  println(i)
  i++
  if (i == 4) {
    break
  }
}
19.CONTINUE  demonstration
fun main() { 
  var i = 0
while (i < 10) 
    {
  if (i == 4) 
    {
    i++
    continue   
  }
  println(i)
  i++
}  
}
20.RANGE  demonstration
fun main() { 
for (n in 5..15) {
  println(n)
} 
}
21.ARRAY  demonstration
fun main() { 
val  cse = arrayOf("CSE A", "CSE B", "CSE C", "CSE D")
println(cse.size)  // check array length or size
for (x in cse) 
{
  println(x)          
 }
println(cse[0])    // You can access an array element by referring to the index number, inside square brackets

if ("CSE B" in cse) 
{
  println("It exists!") 
} 
    else 
{
  println("It does not exist.")  
 }    
 }