gsd-questions/todten/GSDSolution.java

/**
 *
 * @author todten
 */
import java.math.*;
import java.util.*;

public class GSDSolution {

    /* Main Program */
    public static void main(String[] args) {
        
        int someCows = 10;

        System.out.println(someCows + " cows have " + countLegs(someCows) + " legs \n");

        System.out.println("Calculate Row Vector");
        calcAbsRowVector(inputMatrix);
        
        System.out.println("Merge and Sort Arrays");
        mergeAndSortArrays(input1, input2);

    }

       
    /* Third Exercise */
    
    public static int countLegs(int cows) {
        if (cows == 0) {
            return 0;
        } else {
            return 4 + countLegs(cows - 1);
        }
    }

    /* First Exercise */
    
    static int[][] inputMatrix = new int[][]{
        {2, 2},
        {4, 4},
        {6, 5}};

    public static double[] calcAbsRowVector(int[][] aMatrix) {

        double[] result = new double[aMatrix.length];
        double temp = 0.0;

        for (int i = 0; i < aMatrix.length; i++) {
            for (int j = 0; j < aMatrix[i].length; j++) {
                temp = temp + Math.pow(aMatrix[i][j], 2);
                //System.out.println(" I = " + i + " J = " + j + " Temp = " + temp);
            }
            result[i] = Math.sqrt(temp);
            temp = 0.0;
            //System.out.println(" Result at I " + i + " Result " + result[i]);
        }

        return result;
    }

    /* Second Exercise */
    
    static int[] input1 = new int[]{2, 7, 5, 34};
    static int[] input2 = new int[]{3, 48, 4, 72};
    
    public static int[] mergeAndSortArrays(int[] firstArray, int[] secondArray) {

        int[] resultArray = new int[firstArray.length * 2];
        /* OK, both Arrays are the same size */

        int offset = firstArray.length;

        for (int i = 0; i < firstArray.length; i++) {
            resultArray[i] = firstArray[i];
        }
        for (int i = 0; i < secondArray.length; i++) {
            resultArray[i + offset] = secondArray[i];
        }
        
        
        
        
        /* Just for debugging */
        System.out.println("Result Array " + Arrays.toString(resultArray));
        
        /*
         * Die haeufigste Antwort wird die Verwendung der build - in Funktion 
         * von Java zum Sortieren von Arrays sein
        */
        
        Arrays.sort(resultArray);
        
         /*
         * Dann nachfragen und den Bewerber das Array manuell mit einem 
         * Algorithmus seiner Wahl (z.B. Quicksort oder einfache Maximumssuche)
         * sortieren lassen
        */
        
        /* Just for debugging */
        System.out.println("Sorted Result Array " + Arrays.toString(resultArray));
        
        return resultArray;
    }
}