Multiplication is 100 times faster than Math.pow()

cube.java

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		double a = Math.random();
		double a3;
		int n = 10000000;
		
		long start = System.currentTimeMillis();
		for (int i = 0; i < n; i++) a3 = Math.pow(a, 3);
		long stop = System.currentTimeMillis();
		System.out.println((stop-start)/1000.0);

		start = System.currentTimeMillis();
		for (int i = 0; i < n; i++) a3 = a*a*a;
		stop = System.currentTimeMillis();
		System.out.println((stop-start)/1000.0);
	}
}

Run on ideone.com:

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