Add attributes for curriculum

Co-authored-by: EduardDurech <39579228+EduardDurech@users.noreply.github.com>

reasoning_gym/arithmetic/chain_sum.py

@@ -2,6 +2,7 @@ import random
 from dataclasses import dataclass
 from typing import Optional
 
+from ..coaching import AttributeType, BaseCurriculum, RangeAttributeDefinition
 from ..factory import ProceduralDataset, register_dataset
 
 
@@ -112,5 +113,36 @@ class ChainSum(ProceduralDataset):
         return expression, result
 
 
+class ChainSumCurriculum(BaseCurriculum):
+    def __init__(self):
+        super().__init__(ChainSumCurriculum.__name__, ChainSumConfig)
+
+        # Define attributes
+        self._define_attributes(
+            (
+                RangeAttributeDefinition(
+                    name="num_terms",
+                    levels=[2, 3, 4, 5],
+                    default_level=0,  # Start with 2 terms
+                    description="Maximum number of terms in the expression",
+                    attr_type=AttributeType.APPEND,
+                    min_value=2,  # Ensure at least 2 terms
+                    lower_field_name="min_terms",
+                    upper_field_name="max_terms",
+                ),
+                RangeAttributeDefinition(
+                    name="num_digits",
+                    levels=[1, 2, 4, 10],
+                    default_level=0,  # Start with 1-digit numbers
+                    description="Number of digits in each operand",
+                    attr_type=AttributeType.APPEND,
+                    min_value=1,  # Ensure numbers are at least 1 digit
+                    lower_field_name="min_digits",
+                    upper_field_name="max_digits",
+                ),
+            )
+        )
+
+
 # Register the dataset
 register_dataset("chain_sum", ChainSum, ChainSumConfig)