Added solution to #206

Author: Kavisha20340

leetcode/cpp/linkedlist/206.cpp

@@ -0,0 +1,27 @@
+// Leetcode Problem #206
+// Title : Reverse Linked list
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     ListNode *next;
+ *     ListNode() : val(0), next(nullptr) {}
+ *     ListNode(int x) : val(x), next(nullptr) {}
+ *     ListNode(int x, ListNode *next) : val(x), next(next) {}
+ * };
+ */
+class Solution {
+public:
+    ListNode* reverseList(ListNode* head) {
+        ListNode *p=head,*q=NULL,*r=NULL; 
+        while(p!=NULL)
+        {
+            r=q;
+            q=p;
+            p=p->next;
+            q->next=r;
+        }
+        head=q;   
+        return head;
+    }
+};