[easy] 1768. Merge Strings Alternately

Author: joffilyfe

1768.py

@@ -0,0 +1,49 @@
+import unittest
+
+# https://leetcode.com/problems/merge-strings-alternately/
+
+
+class Solution:
+    """The intuition behind this problem is simple:
+    1) Use two pointers to track what is the current letter from each strings
+    2) Loop while each pointer is less than its pointer size
+    3) Append the string with letters in the order: word1 then word2
+    4) Return the result string
+    """
+
+    def mergeAlternately(self, word1: str, word2: str) -> str:
+        word1Size = len(word1)
+        word2Size = len(word2)
+        word1Pointer = 0
+        word2Pointer = 0
+
+        res = ""
+
+        while word1Pointer < word1Size or word2Pointer < word2Size:
+            if word1Pointer < word1Size:
+                res += word1[word1Pointer]
+                word1Pointer += 1
+
+            if word2Pointer < word2Size:
+                res += word2[word2Pointer]
+                word2Pointer += 1
+
+        return res
+
+
+class Tests(unittest.TestCase):
+    def test_one(self):
+        word1 = "abc"
+        word2 = "pqr"
+
+        self.assertEqual(Solution().mergeAlternately(word1, word2), "apbqcr")
+
+    def test_two(self):
+        word1 = "ab"
+        word2 = "pqrs"
+
+        self.assertEqual(Solution().mergeAlternately(word1, word2), "apbqrs")
+
+
+if __name__ == "__main__":
+    unittest.main()

README.md

@@ -38,6 +38,7 @@
 | 1710.py        |                             |                                                                                                            |
 | 1742.py        |                             |                                                                                                            |
 | 1748.py        |                             |                                                                                                            |
+| 1768.py        | String / Two pointers       | <https://leetcode.com/problems/merge-strings-alternately>                                                  |
 | 1832.py        |                             |                                                                                                            |
 | 1859.py        |                             |                                                                                                            |
 | 1876.py        |                             |                                                                                                            |