Exercises

• Exercise 1:

Define a generic class Point so that it is applicable whatever the type of its coordinates (int or double).






Solution :




class Point<T> {

  T x, y;

  Point(this.x, this.y);

}

 

void main() {

  var p1 = Point<int>(1, 4);

  var p2 = Point<double>(1.2, 4.5);

}





• Exercise 2:

Use a generic method that return the number of occurence of an element in a given list. Test it with 3 lists of type int , double and string.






Solution :




int occurence<T>(List<T> list, T element) {

  int res = 0;

  for (T e in list) {

    if (e == element) res++;

  }

  return res;

}

 

void main() {

  var li = <int>[1, 4, 5, 1, 2, 4, 5, 4],

      ld = <double>[1.4, 3.14, 3.14, 3.6, 6.1],

      ls = <String>["flutter", "dart", "apps"];

  print(occurence(li, 4));

  print(occurence(ld, 3.14));

  print(occurence(ls, "apps"));

}





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