Javakurs/Übungsaufgaben/Fibonacci/Musterlösung

public class FibonacciNumbers {

  public static void main(String args[]) {

    printfibonacci(-1, 8);
  }

  
  /*outputs fibonacci numbers from argument one to argument two*/
  public static void printfibonacci( int start, int end ) {

    for( int i= start; i < end; i++ ) {

      System.out.println( "fibonacci("+ i +") = "+ fibonacci(i) );
    }
  }

  /* calculates a fibonacci number of n */
  public static int fibonacci( int n ) {                              
  
    if ( 0 == n ) {
      return 0;
    }

    if ( 1 == n ) {
      return 1;
    }

    if (n > 1) {
      return fibonacci( n-1 ) + fibonacci( n-2 );
    } else {
      System.out.println ( "Error! Fibonacci undefined for negativ "+
                           "values");
       return -1;
      }
  }

}

Alternative Lösung

public class Fibonacci {

	
	public static void main(String[] args) {
		
			System.out.print(fibonacci(5));
	}
	public static int fibonacci(int n){
		if (n<0){
			System.out.print("Du hast eine negative Zahl eingegeben:");
		}else{
		if(n>1){
			n = fibonacci(n-1) + fibonacci(n-2); 
		}}
		return n;
	}
}