func main()
	var n: int :: cui@inputInt()
	var m: int :: cui@inputInt()
	var k: int :: cui@inputInt()
	var map: [][]dict<int, bool> :: #[n, n]dict<int, bool>
	for a(0, n - 1)
		for b(0, n - 1)
			do map[a][b] :: #dict<int, bool>
		end for
	end for
	for(1, m)
		var a: int :: cui@inputInt() - 1
		var b: int :: cui@inputInt() - 1
		var c: int :: cui@inputInt()
		do map[a][b].add(c, true)
		do map[b][a].add(c, true)
	end for
	
	var exists: [][]bool :: #[k + 1, n]bool
	do exists[0] :: [true].repeat(n)
	for i(0, k - 1)
		var d: int :: cui@inputInt()
		for a(0, n - 1)
			if(exists[i][a])
				for b(0, n - 1)
					if(map[a][b].get(d, &))
						do exists[i + 1][b] :: true
					end if
				end for
			end if
		end for
	end for
	var ans: []int :: #[0]int
	for i(0, n - 1)
		if(exists[k][i])
			do ans :~ [i + 1]
		end if
	end for
	do cui@print("\{^ans}\n")
	for i(0, ^ans - 1)
		do cui@print("\{ans[i]}" ~ (i = ^ans - 1 ?("\n", " ")))
	end for
end func