Pot

package uzgwafzuwrf;

public class potenzieren {

    public static void main(String [] args){
        System.out.println(berechne(2,3));
        System.out.println(berechne2(2,3));
    }

    public static int berechne(int x, int k){
        if(k == 0){
            return 1;
        }else if(k == 1){
            return x;
        }else if(k > 1){
            return x*berechne(x, k-1);
        }else{
            return -1;
        }
    }

    public static int berechne2(int x, int k){
        if(k==0){
            return 1;
        }else if(k==1){
            return x;
        }else if(k>1 && (k%2 == 0)){
            return (berechne2(x*x, k/2));
        }else if(k > 1 && (k%2 == 1)){
            return x*(berechne2(x*x, (k-1)/2));
        }else{
            return -1;
        }
    }

}