A Simple Integer Power Function

				
//**************************************
// Name: A Simple Integer Power Function
// Description:Non floating-point exponent.
Computes the result of x^y where x and y are integers and fp arithmetic is not supported (e.g. CLDC 1.0)
// By: Happy Newt
//
// Inputs:int x, int y
//
// Returns:returns x^y as a (long) number
NOTE: y is treated as an unsigned int
//
// Assumes:y is treated as UNSIGNED.
In the case where x^y is greater than Long.MAX_VALUE, the result will overflow in the same way as an integer * , + or - operation. (A wraparound effect.) So watch out for that.
This is a really tiny little function from the com.merrynewton.util.nonfp.IntMath class, from the MNMU1.0 class library
The whole library is free to use, covered by a BSD licence.
//
//This code is copyrighted and has// limited warranties.Please see http://www.Planet-Source-Code.com/vb/scripts/ShowCode.asp?txtCodeId=5301&lngWId=2//for details.//**************************************

// RAISE THE FIRST ARGUMENT TO THE POWER OF THE SECOND
// b will be treated as an UNSIGNED integer
 public static long power(int x,int y){
 long p=1;
 long b=((long)y)&0x00000000ffffffffL;
 // bits in b correspond to values of powerN
 // so start with p=1, and for each set bit in b, multiply corresponding table entry
 long powerN=x;
 while(b!=0){
 if((b&1)!=0) p*=powerN;
 b>>>=1;
 powerN=powerN*powerN;
 }
 return p;
 } // power