CREATE TABLE table_203_105 (id DECIMAL, "name" TEXT, "street address" TEXT, "years as tallest" TEXT, "height\ ft  ( m ) " TEXT, "floors" DECIMAL)

which building has the same number of floors as the lumber exchange building ?
SELECT "name" FROM table_203_105 WHERE "name" <> 'lumber exchange building' AND "floors" = (SELECT "floors" FROM table_203_105 WHERE "name" = 'lumber exchange building')
SELECT "name" FROM "table_203_105" WHERE "floors" = (SELECT "floors" FROM "table_203_105" WHERE "name" = 'lumber exchange building') AND "name" <> 'lumber exchange building'