feat: 186. Reverse Words in a String II

Author: fghpdf

create_py_solution.py

@@ -12,4 +12,6 @@
 
 filePath = os.path.join('./py', folderName, folderName+'.py')
 if not os.path.exists(filePath):
-  with open(filePath, 'w'): pass
+  with open(filePath, 'w'): pass
+
+os._exit(0)

py/reverse_words_in_a_string_ii/reverse_words_in_a_string_ii.py

@@ -0,0 +1,38 @@
+from typing import List
+import unittest
+
+class Solution:
+    def reverseWords(self, s: List[str]) -> None:
+        """
+        Do not return anything, modify s in-place instead.
+        """
+        self.swap(s, 0, len(s)-1)
+
+        # reverse word
+        wordStart = 0
+        for i in range(len(s)):
+          if s[i] == " ":
+            self.swap(s, wordStart, i-1)
+            wordStart = i+1
+          elif len(s)-1 == i:
+            self.swap(s, wordStart, i)
+
+    def swap(self, s, start, end) -> None:
+      while start < end:
+        s[start], s[end] = s[end], s[start]
+        start += 1
+        end -= 1
+        
+
+class TestSolution(unittest.TestCase):
+    def testReverseWords(self):
+        sol = Solution()
+        s = ["t","h","e"," ","s","k","y"," ","i","s"," ","b","l","u","e"]
+        sol.reverseWords(s)
+        self.assertEqual(s, ["b","l","u","e"," ","i","s"," ","s","k","y"," ","t","h","e"])
+        s = ["a"]
+        sol.reverseWords(s)
+        self.assertEqual(s, ["a"])
+
+if __name__ == '__main__':
+    unittest.main()