Merge Sort

public class MergeSort { 
 
    public static void main(String[] args) { 
 
        int[] input; 
        int length; 
 
        String inputString = "4143675351981074"; 
        length = inputString.length(); 
 
        input = new int[length]; 
        for (int i = 0; i < length; i++) { 
            input[i] = Character.getNumericValue(inputString.charAt(i)); 
        } 
 
        System.out.println("Unsorted list:"); 
        printList(input); 
        System.out.println(); 
 
        input = sort(input); 
 
        System.out.println("Sorted list:"); 
        printList(input); 
 
    } 
 
    public static int[] sort(int[] initial) { 
 
        int size = initial.length; 
 
        if (size == 1) { 
            return initial; 
        } 
 
        int[] first = new int[size / 2]; 
        int[] second = new int[size - (size / 2)]; 
        System.out.println("Split:"); 
        for (int i = 0; i < first.length; i++) { 
            first[i] = initial[i]; 
            System.out.print(initial[i] + " "); 
        } 
        System.out.println(); 
        for (int j = 0; j < second.length; j++) { 
            second[j] = initial[j + (size / 2)]; 
            System.out.print(initial[j + (size / 2)] + " "); 
        } 
        System.out.println(); 
        System.out.println(); 
 
        return merge(sort(first), sort(second)); 
    } 
 
    public static int[] merge(int[] first, int[] second) { 
 
        System.out.println("Merging:"); 
        for (int a = 0; a < first.length; a++) { 
            System.out.print(first[a] + " "); 
        } 
        System.out.print("and "); 
        for (int b = 0; b < second.length; b++) { 
            System.out.print(second[b] + " "); 
        } 
        System.out.println(); 
        System.out.println(); 
 
        int[] merged = new int[first.length + second.length]; 
        int pointer1 = 0; 
        int pointer2 = 0; 
        for (int i = 0; i < merged.length; i++) { 
            if (pointer1 == first.length) { 
                merged[i] = second[pointer2]; 
                pointer2++; 
            } 
            else if (pointer2 == second.length) { 
                merged[i] = first[pointer1]; 
                pointer1++; 
            } 
            else if (first[pointer1] < second[pointer2]) { 
                merged[i] = first[pointer1]; 
                pointer1++; 
            } 
            else { 
                merged[i] = second[pointer2]; 
                pointer2++; 
            } 
        } 
 
        System.out.println("Merged:"); 
        for (int j = 0; j < merged.length; j++) { 
            System.out.print(merged[j] + " "); 
        } 
        System.out.println(); 
        System.out.println(); 
 
        return merged; 
    } 
 
    public static void printList(int[] input) { 
        for (int i = 0; i < input.length; i++) { 
            System.out.print(input[i] + " "); 
        } 
        System.out.println(); 
    } 
 
}