first commit

Untitled1.cpp

+// C++ implementation of Shell Sort
+  #include <iostream>
+  using namespace std; 
+  /* function to sort arr using shellSort */
+  int shellSort(int arr[], int n)
+  {
+    // Start with a big gap, then reduce the gap
+    for (int gap = n/2; gap > 0; gap /= 2)
+    {
+      // Do a gapped insertion sort for this gap size.
+      // The first gap elements a[0..gap-1] are already in gapped order
+      // keep adding one more element until the entire array is
+      // gap sorted
+      for (int i = gap; i < n; i += 1)
+      {
+        // add a[i] to the elements that have been gap sorted
+        // save a[i] in temp and make a hole at position i
+        int temp = arr[i];
+  
+        // shift earlier gap-sorted elements up until the correct
+        // location for a[i] is found
+        int j;		
+        for (j = i; j >= gap && arr[j - gap] > temp; j -= gap)
+          arr[j] = arr[j - gap];
+        
+        // put temp (the original a[i]) in its correct location
+        arr[j] = temp;
+      }
+    }
+    return 0;
+  }
+  
+  void printArray(int arr[], int n)
+  {
+    for (int i=0; i < n; i++)
+      cout  <<  arr[i] << " ";
+  }
+  
+  int main()
+  {
+    int arr[] = {6, 17, 28, 1, 3}, i;
+    int n = sizeof(arr)/sizeof(arr[0]);
+  
+    cout << "Array before sorting: \n";
+    printArray(arr, n);
+  
+    shellSort(arr, n);
+  
+    cout << "\nArray after sorting: \n";
+    printArray(arr, n);
+  
+    return 0;
+  }
+