GH-313: solve leetcode 202 (#314)

Author: quang-ph

collections/leetcode/README.md

@@ -230,7 +230,7 @@
 <td>200</td>
 <tr>
 <td>201</td>
-<td>202</td>
+<td>🟢&nbsp;<a href='https://github.com/rain1024/datastructures-algorithms-competitive-programming/tree/main/problems/leetcode202'>202</a></td>
 <td>203</td>
 <td>204</td>
 <td>🟡&nbsp;<a href='https://github.com/rain1024/datastructures-algorithms-competitive-programming/tree/main/problems/leetcode205'>205</a></td>

collections/leetcode/data.yaml

@@ -102,6 +102,9 @@ problems:
 - name: 169
   languages: cpp
   level: easy
+- name: 202
+  languages: python
+  level: easy
 - name: 205
   languages: cpp
   level: medium

problems/leetcode202/.gitignore

@@ -0,0 +1,3 @@
+solution
+*.dSYM
+python/main/__pycache__

problems/leetcode202/README.md

@@ -0,0 +1,10 @@
+# Leetcode Problem 
+
+## Usage
+
+Test program
+
+```
+# Run all tests
+python solution_test.py
+```

problems/leetcode202/data/1.in

@@ -0,0 +1 @@
+19

problems/leetcode202/data/1.out

@@ -0,0 +1 @@
+True

problems/leetcode202/data/2.in

@@ -0,0 +1 @@
+2

problems/leetcode202/data/2.out

@@ -0,0 +1 @@
+False

problems/leetcode202/problem_infos.json

@@ -0,0 +1,9 @@
+{
+  "name": "Leetcode 202. Happy Number",
+  "link": "https://leetcode.com/problems/happy-number/",
+  "tags": [
+    "Hash Table",
+    "Math",
+    "Two Pointers"
+  ]
+}

problems/leetcode202/python/main/solution.py

@@ -0,0 +1,20 @@
+class Solution(object):
+    def isHappy(self, n):
+        """
+        :type n: int
+        :rtype: bool
+        """
+        def get_next(n):
+            total_sum = 0
+            while n > 0:
+                n, digit = divmod(n, 10)
+                total_sum += digit ** 2
+            return total_sum
+
+        seen = set()
+        while n != 1 and n not in seen:
+            seen.add(n)
+            n = get_next(n)
+
+        return n == 1
+        

problems/leetcode202/python/tests/solution_test.py

@@ -0,0 +1,49 @@
+import sys
+import unittest
+from os import listdir
+from os.path import abspath, dirname, join
+
+python_source = dirname(dirname(abspath(__file__)))
+sys.path.append(python_source)
+from main.solution import Solution
+
+test_data_directory = join(dirname(python_source), 'data')
+test_cases = set([data_file.split('.')[0] for data_file in listdir(test_data_directory)])
+
+def read_input(input_file):
+    with open(input_file, 'r') as f:
+        val = int(f.readline().strip())
+    return val
+
+def read_output(output_file):
+    with open(output_file, 'r') as f:
+        k = f.readline().strip()
+        if k == 'True':
+            return True
+        else:
+            return False
+
+class TestSequenceMeta(type):
+    def __new__(mcs, name, bases, dict):
+
+        def gen_test(input_file, output_file):
+            def test(self):
+                solution = Solution()
+                val = read_input(input_file)
+                expected_k = read_output(output_file)
+                actual_k = solution.isHappy(val)
+                self.assertEqual(actual_k, expected_k)
+            return test
+
+        for test_case in test_cases:
+            test_name = f'test_{test_case}'
+            input_file = join(test_data_directory, f'{test_case}.in')
+            output_file = join(test_data_directory, f'{test_case}.out')
+            dict[test_name] = gen_test(input_file, output_file)
+        return type.__new__(mcs, name, bases, dict)
+
+class TestSequence(unittest.TestCase, metaclass=TestSequenceMeta):
+    pass
+
+if __name__ == '__main__':
+    unittest.main()