Merge pull request larissalages#243 from SouravCodery/patch-1

Create 189. Rotate Array.cpp

Author: larissalages

leetcode/cpp/Array/189_rotate_array.cpp

@@ -0,0 +1,31 @@
+class Solution {
+public:
+    void reverse(vector<int> &nums, int startIndex, int endIndex)
+    {
+        //This function reverses the vector for the given start and end Indices of the Vector
+        while(startIndex < endIndex)
+        {
+            int temp = nums[startIndex];
+            nums[startIndex] = nums[endIndex];
+            nums[endIndex] = temp;
+            
+            startIndex++;
+            endIndex--;
+        }
+    }
+    void rotate(vector<int>& nums, int k) 
+    {
+        int length = nums.size(); //Stores the Size of the Vector into the length variable
+        if(k > length)
+        {
+            k %= length;           //Making Sure that the Rotation is within the length of the Vector
+        }
+        if(k == 0 || k == length)   //If k is zero or k is equal to the length of the Vector there is no need to perform operations on it
+            return;
+        
+        //Rotating the Vector with the help of the Reverse Function
+        reverse(nums, 0, length - 1);   
+        reverse(nums, 0, k - 1);        
+        reverse(nums, k, length - 1);
+    }
+};