//
// Description:
//
//      NamedArray defines an "integer array" class in which each
//      object contains an integer array and a (string) name.
//      Extra functionality is provided; see individual method
//      definitions.
//
// Usage:
//
//      See method definitions for usage of individual methods.
//
//      main() tests the other methods:
//      "java NamedArray aName N a1 ... aN" creates two NamedArrays
//              aa, bb (one using each constructor method) with
//              name aName, length N, and elements a1, ... aN and 
//              writes the following to system output:
//                      aa.getName()
//                      aa.getLength()
//                      aa.getElement(i), for i = 0 ... aa.getLength()-1
//                      aa.sumArray() 
//                      aa.productArray() 
//                      bb.getName()
//                      bb.getLength()
//                      bb.getElement(i), for i = 0 ... bb.getLength()-1
//      It is assumed that input arguments are valid (a1 ... aN are
//              integers).
//
public
class NamedArray {

        private String name ;
        private int[] nums ;

        // ---- constructor methods ------------------------------------
        public
        NamedArray(String s, int l) {
                name = s ;
                nums = new int[l] ;
        }

        public
        NamedArray(String s, int[] a) {
                name = s ;
                nums = new int[a.length] ;
                for (int i = 0 ; i < a.length ; i++) {
                        nums[i] = a[i] ;
                }
        }

        // ---- methods to set, retrieve elements ----------------------

        // set element i to n
        public void
        setElement(int i, int n) {
                nums[i] = n ;
        }
        
        // return value of element i
        public int
        getElement(int i) {
                return nums[i] ;
        }

        // return length
        public int
        getLength() {
                return nums.length ;
        }

        // return name
        public String
        getName() {
                return name ;
        }

        // ---- other methods ------------------------------------------

        // return sum of array elements
        public int
        sumArray() {
                int sum = 0 ;
                for (int i = 0 ; i < nums.length ; i++) {
                        sum += nums[i] ;
                }
                return sum ;
        }

        // return product of array elements
        public int
        productArray() {
                int product = 1 ;
                for (int i = 0 ; i < nums.length ; i++) {
                        product *= nums[i] ;
                }
                return product ;
        }

        // ---- main method --------------------------------------------

        public static void
        main(String[] args) {

                NamedArray aa ;
                NamedArray bb ;

                // get name ;
                String name = args[0] ;

                // get length of array
                int l = Integer.parseInt(args[1]) ;

                // get elements
                int[] elems = new int[l] ;
                for (int i = 0 ; i < l ; i++) {
                        elems[i] = Integer.parseInt(args[2+i]) ;
                }

                // construct NamedArray with first constructor
                aa = new NamedArray(name, l) ;
                for (int i = 0 ; i < l ; i++) {
                        aa.setElement(i, elems[i]) ;
                        // note that if we had not needed elems for
                        // the second test, we could have used this:
                        // aa.setElement(Integer.parseInt(args[2+i])) ;
                }

                // construct NamedArray with second constructor
                bb = new NamedArray(name, elems) ;

                // test methods on aa
                System.out.println("Constructed with first method:") ;
                System.out.println("Array name:  " + aa.getName()) ;
                System.out.println("Array length:  " + 
                        aa.getLength()) ;
                System.out.print("Array elements:  ") ;
                for (int i = 0 ; i < aa.getLength() ; i++) 
                        System.out.print(aa.getElement(i) + " ") ;
                System.out.println("") ;
                System.out.println("Sum of elements:  " +
                        aa.sumArray()) ;
                System.out.println("Product of elements:  " +
                        aa.productArray()) ;

                // test methods on bb
                System.out.println("Constructed with second method:") ;
                System.out.println("Array name:  " + bb.getName()) ;
                System.out.println("Array length:  " + 
                        bb.getLength()) ;
                System.out.print("Array elements:  ") ;
                for (int i = 0 ; i < bb.getLength() ; i++) 
                        System.out.print(bb.getElement(i) + " ") ;
                System.out.println("") ;
        }
}