Accepted solution for problem 9 - palindrome number.

main.cpp

@@ -2,6 +2,7 @@
 
 #include "1-two-sum.cpp"
 #include "2-add-two-numbers.cpp"
+#include "9-palindrome-number.cpp"
 
 int main() {
     TwoSumSolution twoSumSolution;
@@ -52,5 +53,8 @@ int main() {
     }
     std::cout << std::endl;
 
+    PalindromeNumberSolution p;
+    std::cout << "Is 1 palindrome? " << p.isPalindrome(1) << std::endl;
+
     return 0;
 }