add linked list pallindrome

Author: akgmage

Linked List/linked_list_pallindrome.cpp

@@ -0,0 +1,33 @@
+
+/**
+ * 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:
+    bool isPalindrome(ListNode* head) {
+        vector<int> contents;
+        while(head != NULL) {
+            int val = head->val;
+            contents.push_back(val);
+            head = head->next;
+        }
+        int low = 0, high = contents.size() - 1;
+        while(low <= high) {
+            if(contents[low] == contents[high]){
+                low++;
+                high--;
+            }
+            else {
+                return false;
+            }
+        }
+        return true;
+    }
+};