Thread: Java is 1000 times faster than c++ on my computer???

Ok, this is driving me batty. I recently had an assignment to implement Floyds algorithm and Dijkstras on a graph with 5403 vertices. (in java) my program was running impossibly slow so I started troubleshooting. As part of that troubleshooting I wrote a 3 level nested for loop in Java, and the same set of loops in C++. The Java version is running 1000 times faster than the C++ version. I just KNOW Java is not 1000 times faster than C++ Can anybody suggest what might be going on here? Here's the code

Code:

In C++:

#include <iostream>
#include <ctime>
using namespace std;

int main(int argc, char *argv[])
{
	unsigned start = time(0);
	cout << "start is " << start << endl;
	int count=0;
    for (int i=0;i<5404;i++)
    {
    	cout << "i = " << i << endl;
    	for (int j=0;j<5404;j++)
    	{
        	for (int k=0;k<5404;k++)
        	{
        		count ++;
        	}
        }
	}
	unsigned finish = time(0);
	unsigned total = finish-start;
	cout << "n^3 took: "<< total << "seconds" <<  endl;
    return 0;
}// end main

Output: 
	.
	.
	.
i = 5400

i = 5401

i = 5402

i = 5403

finish is 1243916727

n^3 took: 323seconds


Java:
public class Main 
{
	public static void main(String[] args)
	{
		int count=0;
		long start = System.currentTimeMillis();
		for(int k=0;k<5404;k++)
		{
			System.out.println( "k= " + k);
			for (int i=0;i<5404;i++)
			{
				for(int j=0;j<5404;j++)
				{
					count++;
				}
			}
		}
		long finish=System.currentTimeMillis();
		long totalTime=(finish-start);
		System.out.println("n^3 took " + totalTime / 1000.0 + " seconds");
		
	}	
} // end main

Output:
	.
	.
	.
k= 5400

k= 5401

k= 5402

k= 5403

n^3 took 0.332 seconds

Just to flesh out the details. My computer is an amd dual core 2.7Ghz with 4Gb Ram running Ubuntu 9.10.

Java is
java version "1.6.0_0"
OpenJDK Runtime Environment (IcedTea6 1.4.1) (6b14-1.4.1-0ubuntu7)
OpenJDK 64-Bit Server VM (build 14.0-b08, mixed mode)

C compiler is:
g++ (Ubuntu 4.3.3-5ubuntu4) 4.3.3
Copyright (C) 2008 Free Software Foundation, Inc.

commands
java Main
g++ main.cpp