Any hints on how to do this?

[Q8iEnG]

Hi mates :)

how are you? I hope everything is all-right.. ;)

I have a small question, it is my HW to be honest

here is the question:
"Write a method that calculates the following equation:
f(x) =
1 if x = 0,1
√ f(x-1) + √ f(x-2) if x > 1
Undefined if x < 0

using Iterative statement"

Here is my attempt:

import java.util.*;

public class Function
{
	public void calculate()
	{
		Scanner scan = new Scanner( System.in );
		int x, x1 = 0;
		
		while(true)
		{
			System.out.println("Enter an integer (or \"00\" to exit) ");
			x = scan.nextInt();
			
			if( x == 00 )
				break;
			else
				if( x == 0 || x == 1)
				{
					System.out.println("f(x) = 1");
				}
				else
					if( x < 0 )
					{
						System.out.println("f(x) is undefined.");
					}
					else
						if( x > 1 )
						{
							x1 = x;
						}
		}
	}
}

see, in the line where ( x > 1 ) I've stopped :\ didn't know what to do!!

Any hints on how to do it?

Thanks :)

[Q8iEnG]

I did it, can anyone tells me if it is OK or not?

import java.util.*;

public class Function
{
	public void calculate()
	{
		Scanner scan = new Scanner( System.in );
		double x = 0;
		double x1 = 0;
		double  sqrt = 0.0;
		double sqrt1 = 0.0;
		
		System.out.println("Enter an integer (or \"0.01\" to exit) ");
		x = scan.nextInt();
		
		while( x != 0.9 )
		{
			
			if( x == 0 || x == 1)
			{
				System.out.println("f(x) = 1");
			}
			else
				if( x < 0 )
				{
					System.out.println("f(x) is undefined.");
				}
				else
				{
					x1 = x;
					
					while( true )
					{
						x1 = x1 - 1;
						x = x - 2;
						if( x < 0 || x1 < 0 )
						{
							System.out.println("f(x) is undefined.");
							break;
						}
						
						if( x == 1 || x == 0 )
						{
							sqrt = Math.sqrt(x);
						}
						
						if( x1 == 1 || x1 == 0 )
						{
							sqrt1 = Math.sqrt(x1);
						}
						
						if( x1 == 1 || x1 == 0 && x == 1 || x == 0)
						{
							sqrt = sqrt + sqrt1;
							System.out.println("f(x) = " + sqrt);
							break;
						}
								
					}
				}
			
			System.out.println("Enter an integer (or \"00\" to exit) ");
			x = scan.nextInt();
		}
	}
}

Thanks :)

[Q8iEnG]

I did it, haha Thanks mates and sorry for bothering :D

this is my final code:

import java.util.*;

public class Function
{
	public void calculate()
	{
		Scanner scan = new Scanner( System.in );
		double x = 0;
		double x1 = 0;
		double  sqrt = 0.0;
		double sqrt1 = 0.0;
		double sum;
		
		System.out.println("Enter an integer (or \"0.1\" to exit) ");
		x = scan.nextInt();
		
		while( x != 0.1 )
		{
			
			if( x == 0 || x == 1)
			{
				System.out.println("f(x) = 1");
			}
			else
				if( x < 0 )
				{
					System.out.println("f(x) is undefined.");
				}
				else
				{
					x1 = x;
					
					while( true )
					{
						x1 = x1 - 1;
						if( x1 < 0 )
						{
							System.out.println("f(x) is undefined.");
							break;
						}
						
						if( x1 == 1 || x1 == 0 )
						{
							sqrt1 = Math.sqrt(x1);
							break;
						}
								
					}
					while( true )
					{
						x = x - 2;
						if( x < 0 )
						{
							System.out.println("f(x) is undefined.");
							break;
						}
						
						if( x == 1 || x == 0 )
						{
							sqrt = Math.sqrt(x);
							break;
						}
					}
					sum = sqrt + sqrt1;
					System.out.println("f(x) = " + sum );
				}
			
			System.out.println("Enter an integer (or \"0.1\" to exit) ");
			x = scan.nextInt();
		}
	}
}