Task: Program Execution
Input (English): 13, 14, ['B', 'm', '5805', '1081', 'X', 'm', 'F', '7607', 'f', 'w', 'H', 'h', 'B', '7731', '4251', 'N', 'Y', 'f', '6737', '3861', '6593']
Output (English): B7731