Java Abstract Array Sum Average

abstract class Arr { int a[]; int n; abstract int Sum(); abstract double Average(); }

class Array extends Arr { Array (int n) { this.n=n; this.a=new int [n]; }

int Sum() { int cem=0; for(int i=0;i<n;i++){ cem=cem+a[i]; } return cem; }

double Average() { double cem=0; for(int i=0;i<n;i++){ cem=cem+a[i]; } return cem / n; }}