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Introduction to Kotlin

The main() Function

The main() function is the starting off point of every Kotlin program and must be included in the code before execution. 

fun main() {
  // Code goes here
}

Print Statements

A print statement outputs values to the output terminal.

Using a println() statement will create a new line in the output terminal after printing values, while a print() statement will not.

println("Greetings, earthling!")
print("Take me to ")
print("your leader.")


/* 
Prints:
Greetings, earthling!
Take me to your leader.
*/

Comments

Comments are used to document what is happening inside of a program and are ignored by the compiler.

A single-line comment is used to write a comment on one line, while a multiline comment is used to write longer comments that span over multiple lines.

// This is a single-line comment


/*
This
comment
uses
multiple
lines
*/

Order of Execution

Code is read, compiled, and executed in top-down order.

fun main() {
  println("I will be printed first.")
  println("I will be printed second.")
  println("I will be printed third.")
}
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