Added is_palindrome.py (TheAlgorithms#8748)

Author: r0sa2

maths/is_palindrome.py

@@ -0,0 +1,34 @@
+def is_palindrome(num: int) -> bool:
+    """
+    Returns whether `num` is a palindrome or not
+    (see for reference https://en.wikipedia.org/wiki/Palindromic_number).
+
+    >>> is_palindrome(-121)
+    False
+    >>> is_palindrome(0)
+    True
+    >>> is_palindrome(10)
+    False
+    >>> is_palindrome(11)
+    True
+    >>> is_palindrome(101)
+    True
+    >>> is_palindrome(120)
+    False
+    """
+    if num < 0:
+        return False
+
+    num_copy: int = num
+    rev_num: int = 0
+    while num > 0:
+        rev_num = rev_num * 10 + (num % 10)
+        num //= 10
+
+    return num_copy == rev_num
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()