Added python solution for 13. Roman to Integer.(Tahanima#101)

Author: Mushfiqur719

Algorithms/Easy/13_RomanToInteger/Solution.py

@@ -0,0 +1,21 @@
+class Solution:
+    def romanToInt(self, s: str) -> int:
+        # Integer values of the roman numbers
+        values = { "I": 1 , "V": 5 , "X": 10 , "L": 50 , "C": 100 , "D": 500 , "M": 1000 }
+
+        num = 0
+
+        left = 0
+
+        size = len(s)
+
+        for i in range(size-1, -1, -1):
+            current = values[s[i]]
+
+            if (current >= left):
+                num += current
+            else:
+                num -= current
+            left = current
+
+        return num