1    /* 
2    A program that plays with arrays. 
3     */
4    
5    package arrayplay;
6    
7    public class Primes {
8    
9        public static void main(String[] args) {
10   
11           int [] primes = new int[4];
12   
13           primes[0] = 2 ;
14           primes[1] = 3;
15           primes[2] = 5;
16           primes[3] = 7;
17   
18           System.out.println("length of primes array = " + primes.length);
19           System.out.println("first prime = " + primes[0]);
20           System.out.println("last prime = " + primes[3]);
21           System.out.println("last prime = " + primes[primes.length-1]);
22   
23           System.out.println("\nThe initial array ...");
24           int i=0;
25           while (i < primes.length) {
26               System.out.println(primes[i]);
27               i=i+1;
28           }
29   
30           int temp = primes[0];
31           primes[0] = primes[primes.length-1];
32           primes[primes.length-1] = temp;
33   
34           System.out.println("\nThe final array ...");
35           for (int x = 0; x<primes.length;x=x+1) {
36               System.out.println(primes[x]);
37           }
38       }
39   }
40