how many teams have used the stadium which hosted the snowboarding at the 2014 winter olympics – men's parallel slalom ?
SELECT DISTINCT COUNT attr_open var_uri attr_close where brack_open dbr_Snowboarding_at_the_2014_Winter_Olympics_–_Men's_parallel_slalom dbp_venue var_x sep_dot var_x dbo_tenant var_uri sep_dot var_x a dbo_Stadium brack_close