package fib;

import java.math.BigInteger;

/**
 * Fibonacci numbers.
 *
 * @author Samuel Rebelsky
 * @author Angeline Namai
 * @version Version 1.0 of October 2004.
 */
 
public class Computer
{
// +-----------+---------------------------------------------------------
// | Observers |
// +-----------+

	/* public long fib(int n)
	{
		long[] values = new long[n+1];
  	 	values[0] = 0;
   		values[1] = 1;
   			for (int i = 2; i <= n; i++)
   			{
      			values[i] = values[i-1] + values[i-2];
   			} // for(int)
   		return values[n];
	} // fib(int)
	*/	

	/**
	 * Compute the nth fibonacci number and return the result as a BigInteger.
 	 */
	public BigInteger fib(int n)
	{
		// Sanity check: Do the easy ones without the array.
		if (n < 2)
			return BigInteger.valueOf(n);
   		BigInteger[] values = new BigInteger[n+1];
		values[0] = BigInteger.valueOf(0);
   		values[1] = BigInteger.valueOf(1);
			for (int i = 2; i <= n; i++)
   			{
      			values[i] = values[i-1].add(values[i-2]);
   			} // for(int)
		return values[n];
	} // fib(int)
	

} // class Computer