this code to show the diff between extend the abstract class and the implementation of it (In dart programming Language)

Extension And Implementation In Dart

/*
Dart Abstraction?
1- Nothing called interface in dart (Interface class)
2- you can only make abstract classes 
3- NO keyword of abstract before method Declaration

4- abstract classes may contains concrete methods and abstract methods
5- abstract methods with no body
6-Normal methods has body

7- normal classes  all of it methods are concrete only

8- if i “extend” the abstract class i must => override only methods without body
class V1 extends good{}

9-  if i “implements”  the abstract class i must override “all methods”  
=> with body and without body
class V2 implements good{}

*/

abstract  class good{
  
  int getint();
  void printInt(){
    print("int is printed");
  }
}


class V1 extends good{
  @override
  int getint()=>4;
}


class V2 implements good{
  @override
  int getint()=>10;
  
  @override
  void printInt(){
    print("must be imp");
  }
}

void main() {
  V1 v1 = V1();
  print(v1.getint());
  v1.printInt();
  
}