Finish problem 0003-longest-substring-without-repeating-characters

problems/0003-longest-substring-without-repeating-characters/solution.py

@@ -0,0 +1,11 @@
+class Solution:
+    def lengthOfLongestSubstring(self, s: str) -> int:
+        hash = {}
+        longest = 0
+        start = 0
+        for idx, char in enumerate(s):
+            if char in hash and hash[char] >= start:
+                start = hash[char] + 1
+            hash[char] = idx
+            longest = max(longest, idx - start + 1)
+        return longest

problems/0003-longest-substring-without-repeating-characters/solution_test.py

@@ -0,0 +1,14 @@
+import pytest
+from solution import Solution
+
+
+@pytest.mark.parametrize(
+    "s,expected",
+    [
+        ("abcabcbb", 3),
+        ("bbbbb", 1),
+        ("pwwkew", 3),
+    ],
+)
+def test_longest_substring(s, expected):
+    assert Solution().lengthOfLongestSubstring(s) == expected