Create dnf-sort.cpp

algorithms/CPlusPlus/Sorting/dnf-sort.cpp

@@ -0,0 +1,55 @@
+#include <bits/stdc++.h>
+using namespace std;
+ 
+// Function to sort the input array,
+// the array is assumed
+// to have values in {0, 1, 2}
+void sort012(int a[], int arr_size)
+{
+    int lo = 0;
+    int hi = arr_size - 1;
+    int mid = 0;
+ 
+    // Iterate till all the elements
+    // are sorted
+    while (mid <= hi) {
+        switch (a[mid]) {
+ 
+        // If the element is 0
+        case 0:
+            swap(a[lo++], a[mid++]);
+            break;
+ 
+        // If the element is 1 .
+        case 1:
+            mid++;
+            break;
+ 
+        // If the element is 2
+        case 2:
+            swap(a[mid], a[hi--]);
+            break;
+        }
+    }
+}
+ 
+// Function to print array arr[]
+void printArray(int arr[], int arr_size)
+{
+    // Iterate and print every element
+    for (int i = 0; i < arr_size; i++)
+        cout << arr[i] << " ";
+}
+ 
+// Driver Code
+int main()
+{
+    int arr[] = { 0, 1, 1, 0, 1, 2, 1, 2, 0, 0, 0, 1 };
+    int n = sizeof(arr) / sizeof(arr[0]);
+ 
+    sort012(arr, n);
+ 
+    printArray(arr, n);
+ 
+    return 0;
+}