1	// Example 4.2 joi/examples/ArrayDemo.java  
     2	//
     3	//
     4	// Copyright 2003 Bill Campbell and Ethan Bolker
     5	
     6	// A class illustrating arrays 
     7	// 
     8	// Build an array of Fibonacci numbers 1, 1, 2, 3, 5, 8, ...
     9	// and play with it. Sample output:
    10	//
    11	// %> java ArrayDemo 8
    12	// Sum first 8 Fibonacci numbers
    13	// 1 1 2 3 5 8 13 21 
    14	// total: 54
    15	//    
    16	// First 8 Fibonacci numbers (reverse order)
    17	// 21 13 8 5 3 2 1 1 
    18	// Every other fib
    19	// 1    1
    20	// 3    2
    21	// 5    5
    22	// 7    13
    23	
    24	public class ArrayDemo 
    25	{
    26	    public static void main( String[] args ) 
    27	    {
    28	        int n = 6; // default 
    29	        if (args.length > 0) {
    30	            n = Integer.parseInt(args[0]);
    31	        }
    32	
    33	        int[] fibs = new int[n]; // declare and create array
    34	
    35	        fibs[0] = fibs[1] = 1;   // fill first two positions
    36	        for ( int i = 2; i < n; i++ ) { // fill the rest
    37	            fibs[i] = fibs[i-1] + fibs[i-2];
    38	        }
    39	        
    40	        // standard idiom for accumulating total of an array
    41	        int total = 0;
    42	        System.out.println("Sum first " + n + " Fibonacci numbers");
    43	        for ( int i = 0; i < n; i++ ) { 
    44	            System.out.print(fibs[i] + " ");
    45	            total += fibs[i];
    46	        }
    47	        System.out.println("\ntotal: " + total);
    48	        System.out.println();
    49	
    50	        System.out.
    51	            println("First " + n + " Fibonacci numbers (reverse order)");
    52	        for ( int i = n-1; i >= 0 ; i-- ) {     
    53	            System.out.print(fibs[i] + " ");
    54	        }
    55	        System.out.println();
    56	
    57	        System.out.println("Every other fib");
    58	        for ( int i = 0; i < n ; i += 2 ) {     
    59	            System.out.println((i+1) + "\t" + fibs[i]);
    60	        }
    61	        System.out.println();
    62	    }
    63	}