feat(env): Word Sequence Reversal curriculum (#313)

* word sequence reversal curriculum

* metadata

reasoning_gym/algorithmic/word_sequence_reversal.py

@@ -5,10 +5,16 @@ from dataclasses import dataclass
 from random import Random
 from typing import Optional
 
+from ..coaching import AttributeType, BaseCurriculum, RangeAttributeDefinition
 from ..data import read_data_file
 from ..factory import ProceduralDataset, register_dataset
 
-QUESTION_TEMPLATE = """Solve the following problem. Provide you answer as a comma-separated list of words with a space after the comma. Reverse this list of words: {question}"""
+QUESTION_TEMPLATE = """Solve the following problem.
+
+Provide you answer as a comma-separated list of words with a space after the comma.
+
+Reverse this list of words: {words}
+"""
 
 
 @dataclass
@@ -42,19 +48,43 @@ class WordSequenceReversalDataset(ProceduralDataset):
         rng = Random(self.seed + idx)
 
         # Select random words
-        num_words = rng.randint(self.config.min_words, self.config.max_words)
+        num_words = min(
+            rng.randint(self.config.min_words, self.config.max_words),
+            len(self.words),
+        )
         word_indices = rng.sample(range(len(self.words)), num_words)
         words = [self.words[i] for i in word_indices]
 
         # Create question and answer
-        question = ", ".join(words)
+        words_str = ", ".join(words)
         answer = ", ".join(reversed(words))
 
         return {
-            "question": f"{QUESTION_TEMPLATE.format(question=question)}",
+            "question": f"{QUESTION_TEMPLATE.format(words=words_str)}",
             "answer": answer,
-            "metadata": {"num_words": num_words, "words": words},
+            "metadata": {"num_words": num_words, "words": words, "difficulty": {"words": num_words}},
         }
 
 
-register_dataset("word_sequence_reversal", WordSequenceReversalDataset, WordSequenceReversalConfig)
+class WordSequenceReversalCurriculum(BaseCurriculum):
+    def __init__(self):
+        super().__init__(WordSequenceReversalCurriculum.__name__, WordSequenceReversalConfig)
+
+        # Define attributes
+        self._define_attributes(
+            RangeAttributeDefinition(
+                name="words",
+                levels=[10, 50, 100, 500],
+                default_level=1,
+                description="Number of words in the list",
+                attr_type=AttributeType.APPEND,
+                min_value=2,
+                lower_field_name="min_words",
+                upper_field_name="max_words",
+            ),
+        )
+
+
+register_dataset(
+    "word_sequence_reversal", WordSequenceReversalDataset, WordSequenceReversalConfig, WordSequenceReversalCurriculum
+)