For Jesal

main.dart

void main() {
  
  Sample newSample = Sample();
  
  print(newSample.counts);
  
  void setToZero () {
//     for (var i = 0; i < newSample.counts.length; i++) {
//                   newSample.counts[i] = 0;
//     }
    
    newSample.counts.forEach((i) => newSample.counts[i-1] = 0);
    
    print(newSample.counts);
  };
  
  setToZero();
  
}


class Sample {
  
  List counts = [1, 2, 3];
  
}