Merge pull request #49 from navjotdadwal/master

sorting in java

Author: SarthakKeshari

Basic Codes/sort.java

@@ -0,0 +1,67 @@
+/*
+question -
+Take 10 numbers as input from the user and sort it
+*/
+
+import java.util.*;  
+class Main
+{
+    void merge(int a[], int l, int m, int r)     // merging the splited sorted arrays
+    {
+        //merging two arrays i.e L and R
+        int n1 = m - l + 1; // size of the first array
+        int n2 = r - m;  // size of the second array
+  
+        int L[] = new int[n1]; // first array
+        int R[] = new int[n2]; // second array
+  
+        for (int i = 0; i < n1; ++i)
+            L[i] = a[l + i];         // assigning values to the first array
+        for (int j = 0; j < n2; ++j)
+            R[j] = a[m + 1 + j];    // assigning values to the second array
+ 
+        int i = 0, j = 0;  // pointers t array L and R respectively
+        int k = l;  // pointer to the main array
+        while (i < n1 && j < n2) {  // merging until i and j not reach end of the array
+            if (L[i] <= R[j]) {
+                a[k++] = L[i++];    
+            }
+            else {
+                a[k++] = R[j++];
+            }
+        }
+        while (i < n1) {  // merging 1st array when 2nd array is completely merged 
+            a[k++] = L[i++];
+        }
+        while (j < n2) {  // merging 2nd array when 1st array is completely merged
+            a[k++] = R[j++];
+        }
+    }
+    void sort(int arr[], int l, int r)         // dividing the array then merging sorted arrays
+    {
+        if (l < r) {
+            int m =l+ (r-l)/2;  // calculating the mid of the array
+            sort(arr, l, m);   // sorting the left part
+            sort(arr, m + 1, r);  // sorting the right part
+            merge(arr, l, m, r);  // merging the left and right part
+        }
+    }
+    public static void main(String args[])
+    {
+        Scanner sc= new Scanner(System.in);
+        int arr[] = new int[10];
+        System.out.print("Enter ten numbers for the array"); 
+        for(int i=0; i<10; i++)  
+        {  
+          arr[i]=sc.nextInt();   // taking input
+        } 
+        Main ob = new Main();
+        ob.sort(arr, 0, arr.length - 1);  // sorting
+  
+        System.out.println("\nSorted array");
+        int n = arr.length;
+        for (int i = 0; i < n; ++i)
+            System.out.print(arr[i] + " ");    // printing the sorted array
+        System.out.println();
+    }
+}