seed: curriculum content

1.solar-system/3.strings/05.the-mirror/index.md

@@ -0,0 +1,43 @@
+---
+type: challenge
+title: "The Mirror"
+xp: 75
+duration: 30
+difficulty: 3
+---
+
+# The Mirror
+
+> **[INCOMING — Mission Control, Earth]**
+>
+> Cadet, a *palindrome* reads the same forwards and backwards.
+> `racecar`. `level`. `madam`.
+>
+> A reverse-slice flips a string in one move:
+>
+> ```python
+> "Hello"[::-1]    # "olleH"
+> ```
+>
+> A string is a palindrome when it equals its reverse. The `==`
+> operator returns `True` or `False` directly.
+>
+> Implement `mirror(s)` that returns a dict with three keys:
+>
+> - `original` — the input
+> - `reversed` — the input reversed
+> - `palindrome` — `True` if equal to its reverse
+>
+> Match case exactly — `racecar` and `RaceCar` are different inputs.
+>
+> [END TRANSMISSION]
+
+## Your Task
+
+In `starter/starter.py`, build the dict using `[::-1]` and `==`.
+
+## Objectives
+
+- `mirror("racecar")["palindrome"]` is `True`
+- `mirror("hello")["palindrome"]` is `False`
+- All three keys correct for any input string

1.solar-system/3.strings/05.the-mirror/starter/starter.py

@@ -0,0 +1,19 @@
+def mirror(s):
+    """Detect if s is a palindrome and return a dict.
+
+    Keys:
+      "original"    — s unchanged
+      "reversed"    — s reversed
+      "palindrome"  — True if s equals its reverse, False otherwise
+
+    Reverse a string with [::-1]:
+      "Hello"[::-1]  -> "olleH"
+
+    mirror("racecar") -> {"original": "racecar",
+                          "reversed": "racecar",
+                          "palindrome": True}
+    mirror("hello")   -> {"original": "hello",
+                          "reversed": "olleh",
+                          "palindrome": False}
+    """
+    pass

1.solar-system/3.strings/05.the-mirror/testing/test_solution.py

@@ -0,0 +1,27 @@
+from solution import mirror
+
+
+def test_palindrome():
+    r = mirror("racecar")
+    assert r == {"original": "racecar", "reversed": "racecar", "palindrome": True}
+
+
+def test_not_palindrome():
+    r = mirror("hello")
+    assert r == {"original": "hello", "reversed": "olleh", "palindrome": False}
+
+
+def test_level():
+    r = mirror("level")
+    assert r["palindrome"] is True
+
+
+def test_andromeda():
+    r = mirror("andromeda")
+    assert r["palindrome"] is False
+    assert r["reversed"] == "ademordna"
+
+
+def test_noon():
+    r = mirror("noon")
+    assert r == {"original": "noon", "reversed": "noon", "palindrome": True}