add testplan for day 8

.gitignore

@@ -1 +1,10 @@
 .DS_Store
+__pycache__
+.pytest_cache
+.coverage
+
+# virtual env
+venv
+
+# testplan report
+report.json

README.md

@@ -0,0 +1,23 @@
+## Hello! 👋
+This is my [Advent of Code 2023](https://adventofcode.com/2023/) project! I code with python and test with [testplan](https://github.com/morganstanley/testplan).
+
+## How to Run
+### testplan
+```sh
+python tests/test_plan.py
+
+# display testplan report
+tpsreport display fromjson report/report.json
+```
+
+### testplan with coverage
+```sh
+python tests/test_plan.py --coverage
+coverage report -m
+coverage html
+
+# now coverage report is under htmlcov/index.html
+```
+
+## License
+See [License](LICENSE)

aoc2023/day8.py

@@ -0,0 +1,40 @@
+class Part1:
+    NODE_KEY='AAA'
+    MATCH_LAMBDA=lambda v: v == 'ZZZ'
+
+    @classmethod
+    def total_steps(cls, instructions, nodes, node_key=NODE_KEY, match_lambda=MATCH_LAMBDA):
+        ''' 
+        get total steps from walking instructions and nodes 
+        using node_key as initial starting node
+        and end when node name matches with match_lambda
+        '''
+        total_steps=0
+
+        while True:
+            for i in range(len(instructions)):
+                total_steps += 1
+                instruction = instructions[i]
+                current_node = nodes[node_key]
+
+                if instruction == 'L':
+                    node_key = current_node[0]
+                else:
+                    node_key = current_node[1]
+
+                if match_lambda(node_key):
+                    return total_steps
+
+class Part2:
+    MATCH_LAMBDA=lambda v: v.endswith('Z')
+
+    @classmethod
+    def get_node_keys(cls, nodes):
+        return [x for x in nodes.keys() if x.endswith('A')]
+
+    @classmethod
+    def total_steps(cls, instructions, nodes, node_keys, match_lambda=MATCH_LAMBDA):
+        min_steps_per_node_key = [Part1.total_steps(instructions, nodes, node_key, match_lambda) for node_key in node_keys] 
+
+        import math
+        return math.lcm(*min_steps_per_node_key)