package mergeSort;

public class merge {
        static int zaehler = 0;


    public static int[] combine(int[] a, int[] b) {
        int[] c = new int[a.length + b.length];
        int i_a = 0;
        int i_b = 0;

        for (int i = 0; i < c.length; i++) {
            if (i_b < b.length && i_a < a.length) {
                if (a[i_a] <= b[i_b]) {
                    c[i] = a[i_a];
                    i_a++;
                }
                else {
                    c[i] = b[i_b];
                    i_b++;
                }
            }
            else if (i_b < b.length ) {
                c[i] = b[i_b];
                i_b++;
            }
            else {
                c[i] = a[i_a];
                i_a++;
            }
        }
        return c;
    }


    public static int[] split(int[] c) {
        printArray(c);

        if (c.length == 0 || c.length == 1) {
            return c;
        }
        if (c.length == 2) {
            if (istSortiert(c) == true) {
                return c;
            }
            else {
                invertiere(c);
                return c;
            }
        }
        int m = c.length / 2;

        int[] a = new int[m];
        int[] b = new int[c.length - m];


        for (int i = 0; i < a.length; i++) {
            if (c[i] != 0 ) {
                a[i] = c[i];

            }
        }
        for (int i = 0; i < b.length; i++) {
            if (c[i] != 0) {
                b[i] = c[m + i];
            }
        }

        printArray(a);
        printArray(b);
        int[] d = combine(split(a), split(b));
        return d;
    }


    public static boolean istSortiert(int[] a) {
        if (a.length == 1) {
            return true;
        }
        if(a[0] <= a[1]) {
            return true;
        }
        else {
            return false;
        }
    }

    public static int[] invertiere(int[] a) {
        int z = a[0];
        a[0] = a[1];
        a[1] = z;
        return a;
    }

    public static void printArray(int[] a) {
        String text = "";
        for (int i = 0; i < a.length; i++) {
            text += "[" + a[i] + "] ";
        }
        System.out.println(text);
    }

    public static void main(String[] args) {

        int[] c = {3,6,2,7,1,8,2,9,3,7,4,3,8,4,1,7,3,7};
        int[] f = split(c);
        printArray(f);
        System.out.println(merge.zaehler);
    }

}