feat: PalindromeNumber Solution Added

README.md

@@ -11,5 +11,6 @@ Code is easy to understand, documentation is pretty, and program performance is
 | Num | Problem | Solution | Time \| Space Complexity | Difficulty |
 |-----|---------|----------|--------------------------|------------|
 | 7 | [Reverse Integer](https://leetcode.com/problems/reverse-integer/) | [Code](./src/ReverseInteger/Solution.cpp) | O(log(n)) \| O(1) | Easy |
+| 9 | [Palindrome Number](https://leetcode.com/problems/palindrome-number/) | [Code](./src/PalindromeNumber/Solution.cpp) | O(log(n)) \| O(log(n)) | Easy |
 | 13 | [Roman to Integer](https://leetcode.com/problems/roman-to-integer/) | [Code](./src/RomanToInteger/Solution.cpp) | O(n) \| O(1) | Easy |
 | 14 | [Longest Common Prefix](https://leetcode.com/problems/longest-common-prefix/) | [Code](./src/LongestCommonPrefix/Solution.cpp) | O(n) \| O(n) | Easy |

src/PalindromeNumber/README.md

@@ -0,0 +1,33 @@
+# Palindrome Number
+
+LeetCode [source](https://leetcode.com/problems/palindrome-number/)
+
+## Solution
+
+### Intuition
+
+The challenge with this problem is that you're not allowed to use any string. You have to take the integer and come up with a solution that doesn't employ string or any of its methods. From the first glance, what was apparent is that we'll need a data structure to hold the individual integers for comparison.
+
+### Algorithm
+
+Details of the the algorithm for the solution is as follows:
+
+1. If it's a single digit, then it's a Palindrome Number.
+2. Ignore any negative integers.
+3. For all other types of integers, pop each digit and store them in a vector in order.
+4. Compare the **(n + i)th** integer with **(vector.size() - 1 - i)th** integer.
+5. If this comparisos fails (i.e. **comparison == false**) return **false**.
+6. Else continue the comparisons until **i** reaches the middle of the vector. If no **false** was return before, it means all the comparisons were **true** and therefore, the integer is a palindrome.
+
+### Complexity Analysis
+
+* Time Complexity: **O(log⁡(n))**
+* Space Complexity: **O(log⁡(n))**
+
+### AC Result
+
+Test case result: **11509 / 11509 test cases passed**
+
+| Status | Runtime | Memory |
+|--------|---------|--------|
+| Accepted | 36 ms | 11.7 MB |

src/PalindromeNumber/Solution.cpp

@@ -0,0 +1,56 @@
+// Solution by Imtiaz Ahmed (Github: tiazahmd)
+
+#include <iostream>
+#include <vector>
+
+#include "../Test.h"
+
+using namespace std;
+using namespace leetcode;
+
+class Solution {
+public:
+  bool isPalindrome(int x) {
+    if (x >= 0 && x < 10) {
+      return true;
+    } else if (x >= 10) {
+      vector<int> vec;
+      long div = 10;
+      int num = 0;
+      int temp = x;
+
+      while (temp != 0) {
+        num = temp % div;
+        temp = temp / div;
+        vec.push_back(num);
+      }
+
+      for (int i = 0; i < vec.size(); i++) {
+        if (i == vec.size() - 1)
+          return true;
+        else if (vec[i] != vec[vec.size() - 1 - i])
+          return false;
+      }
+
+    } else {
+      return false;
+    }
+
+    return false;
+  };
+};
+
+int main() {
+
+  Solution s;
+
+  test("Test case: ", s.isPalindrome(121), true);
+  test("Test case: ", s.isPalindrome(120), false);
+  test("Test case: ", s.isPalindrome(-121), false);
+  test("Test case: ", s.isPalindrome(11), true);
+  test("Test case: ", s.isPalindrome(9), true);
+  test("Test case: ", s.isPalindrome(0), true);
+  test("Test case: ", s.isPalindrome(10022001), true);
+  test("Test case: ", s.isPalindrome(1001), true);
+  return 0;
+}