Question: who won the gold medal for men's halfpipe
[{'answer': 'Gian Simmen'}, {'answer': 'Ross Powers', 'provenance': [{'wikipedia_id': '6642016', 'title': 'List of Olympic medalists in snowboarding', 'start_paragraph_id': 2, 'start_character': 209, 'end_paragraph_id': 2, 'end_character': 220, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Shaun White', 'provenance': [{'wikipedia_id': '6642016', 'title': 'List of Olympic medalists in snowboarding', 'start_paragraph_id': 2, 'start_character': 66, 'end_paragraph_id': 2, 'end_character': 77, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Iouri Podladtchikov'}]