Merge pull request #31 from satishguptaji/patch-3

File for rotation checking

Author: ashish-ratn

check-sort-rotate.cpp

@@ -0,0 +1,67 @@
+// C++ implementation of above approach 
+#include <bits/stdc++.h> 
+using namespace std; 
+  
+// Function to check if it is possible 
+bool isPossible(int a[], int n) 
+{ 
+    // step 1 
+    if (is_sorted(a, a + n)) { 
+        cout << "Possible" << endl; 
+    } 
+  
+    else { 
+  
+        // break where a[i] > a[i+1] 
+        bool flag = true; 
+        int i; 
+        for (i = 0; i < n - 1; i++) { 
+            if (a[i] > a[i + 1]) { 
+                break; 
+            } 
+        } 
+        // break point + 1 
+        i++; 
+  
+        // check whether the sequence is 
+        // further increasing or not 
+        for (int k = i; k < n - 1; k++) { 
+            if (a[k] > a[k + 1]) { 
+                flag = false; 
+                break; 
+            } 
+        } 
+  
+        // If not increasing after break point 
+        if (!flag) 
+            return false; 
+  
+        else { 
+  
+            // last element <= First element 
+            if (a[n - 1] <= a[0]) 
+                return true; 
+  
+            else
+                return false; 
+        } 
+    } 
+} 
+  
+// Driver code 
+int main() 
+{ 
+  
+    int arr[] = { 3, 1, 2, 2, 3 }; 
+    int n = sizeof(arr) / sizeof(arr[0]); 
+  
+    if (isPossible(arr, n)) 
+        cout << "Possible"; 
+  
+    else
+        cout << "Not Possible"; 
+  
+    return 
+0; 
+} 
+