program to create a function that prints a message

// writing function outside main function.
void printName(){
  print("My name is Raj Sharma. I am from function.");
}
// this is our main function.
void main(){
  printName();
}

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program to create a function that finds sum of two numbers

 void add(int num1, int num2){
  int sum = num1 + num2;
   print("The sum is $sum");
}

void main(){
  add(10, 20);
}

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program to create a function that calculates simple interest

// function that calculate interest
void calculateInterest(double principal, double rate, double time) {
  double interest = principal * rate * time / 100;
  print("Simple interest is $interest");
}

void main() {
  double principal = 5000;
  double time = 3;
  double rate = 3;
  calculateInterest(principal, rate, time);
}

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program to create a function that returns a String

void main() {
  String name = primeMinisterName();
  print("The Name from function is $name.");
}

String primeMinisterName() {
  return "John Doe";
}

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program to create a function that has a optional parameter

void printInfo(String name, String gender, [String title = "sir/ma'am"]) {
  print("Hello $title $name your gender is $gender.");
}

void main() {
  printInfo("John", "Male");
  printInfo("John", "Male", "Mr.");
  printInfo("Kavya", "Female", "Ms.");
}

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example of function having a named parameter

void printInfo({String? name, String? gender}) {
  print("Hello $name your gender is $gender.");
}

void main() {
  // you can pass values in any order in named parameters.
  printInfo(gender: "Male", name: "John");
  printInfo(name: "Sita", gender: "Female");
  printInfo(name: "Reecha", gender: "Female");
  printInfo(name: "Reecha", gender: "Female");
  printInfo(name: "Harry", gender: "Male");
  printInfo(gender: "Male", name: "Santa");
}

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program to create a function having required parameter

void printInfo({required String name, required String gender}) {
  print("Hello $name your gender is $gender.");
}

void main() {
  // you can pass values in any order in named parameters.
  printInfo(gender: "Male", name: "John");
  printInfo(gender: "Female", name: "Suju");
}

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program to create a anonymous function

void main() {
  const fruits = ["Apple", "Mango", "Banana", "Orange"];

  fruits.forEach((fruit) {
    print(fruit);
  });
}

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