add leetcode 13

leetcode/13.py

@@ -0,0 +1,18 @@
+# translate roman number strings to int
+
+
+class Solution:
+    def remanToInt(self, s: str) -> int:
+        roman_map = {"I": 1, "V": 5, "X": 10, "L": 50, "C": 100, "D": 500, "M": 1000}
+        num = 0
+        prev_value = 0
+
+        for char in reversed(s):
+            value = roman_map[char]
+            if value < prev_value:
+                num -= value
+            else:
+                num += value
+            prev_value = value
+
+        return num