Update insertion-sort.java

The advantage of this code over the previous one is that first of all, it takes user-defined input rather than predefined, and also it has a more user-friendly way of understanding algo for every beginner or pro because you can comment out a few lines of code to see how the result is being calculated stepwise.

algorithms/Java/sorting/insertion-sort.java

@@ -1,29 +1,59 @@
 
-import java.util.Arrays;
-
+import java.util.Scanner;
+//uncomment to see steps working....
 public class InsertionSort {
-	static int[] nums = { 12, 43, 2, 4, 1, 0, -23, -93 };
 
-	public static void main(String[] args) {
-		System.out.println("Before sorting " + Arrays.toString(nums));
-		sort(nums);
-	}
+    public void InsSort(int arr []) {
+        int temp;
 
-	public static void sort(int[] nums) {
-		int i = 1;
-		while (i < nums.length) {
-			int temp, j;
-			temp = nums[i];
-			j = i;
+        for(int i=1;i<arr.length;i++){
+            /*System.out.println("\nPass "+(i)+" gives us -> ");
+            System.out.print("\nCurrent ->"+arr[i]);
+            System.out.print("\nPrevious ->"+arr[i-1]);*/
+            if(arr[i]<arr[i-1]){
+                for(int j=1;j>0;j++){
+                    if(j>i){break;}
+                    //System.out.print("\nExchange -> Yes");
+                    while (arr[i-j+1]<arr[i-j]){
+                        temp=arr[i-j];
+                        arr[i-j]=arr[i-j+1];
+                        arr[i-j+1]=temp;
+                        /*if(j>i-1){break;}                                 //done to eliminate error on line 24 for (i-j-1)=(-1)
+                        System.out.print("\nUpdated Current ->"+arr[i-j]);
+                        System.out.print("\nUpdated Previous ->"+arr[i-j-1]);*/
+                    }
+                }
+            }else{//System.out.print("\nExchange -> No");
+            }
+            /*System.out.println("\n");
+            for(int k=0;k<arr.length;k++){
+                System.out.print(arr[k]+" ");
+            }
+            System.out.print("\n");*/
+        }
+    }
+    public void Printarray(int arr []) {                                         //Function to print array
+        for(int j=0;j<arr.length;j++){
+            System.out.print(arr[j]+" ");
+        }
+    }
 
-			while (j > 0 && nums[j - 1] > temp) {
-				nums[j] = nums[j - 1];
-				j--;
-			}
-			nums[j] = temp;
-			i++;
-		}
-		System.out.println("After Sorting " + Arrays.toString(nums));
-
-	}
-}
+    public static void main(String[] args) {
+        int len;
+        
+        InsertionSort obj = new InsertionSort();
+        Scanner scan = new Scanner(System.in);
+        System.out.print("No. of elements in array -> ");
+        len = scan.nextInt();
+        int array[] = new int[len];
+        for(int i=0;i<len;i++){
+            array[i]=scan.nextInt();
+        }
+        scan.close();
+        System.out.print("\nHence, we have the input array as -> [ ");
+        obj.Printarray(array);System.out.print("]");
+        obj.InsSort(array);
+        System.out.print("\nHence, Sorted array using Insertion sort is -> [ ");
+        obj.Printarray(array);System.out.print("]");
+    }
+}