/*
C#: The Complete Reference
by Herbert Schildt
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Indexers don't have to operate on actual arrays.
using System;
class PwrOfTwo {
/* Access a logical array that contains
the powers of 2 from 0 to 15. */
public int this[int index] {
// Compute and return power of 2.
get {
if((index >= 0) && (index < 16)) return pwr(index);
else return -1;
}
// there is no set accessor
}
int pwr(int p) {
int result = 1;
for(int i=0; i<p; i++)
result *= 2;
return result;
}
}
public class UsePwrOfTwo {
public static void Main() {
PwrOfTwo pwr = new PwrOfTwo();
Console.Write("First 8 powers of 2: ");
for(int i=0; i < 8; i++)
Console.Write(pwr[i] + " ");
Console.WriteLine();
Console.Write("Here are some errors: ");
Console.Write(pwr[-1] + " " + pwr[17]);
Console.WriteLine();
}
}
