func main()
	var n: int :: cui@inputInt()
	var dic: dict<int, int> :: #dict<int, int>
	var ans: int :: 0
	for(0, n - 2)
		for i(0, 1)
			var a: int :: cui@inputInt()
			var num: int :: dic.get(a, &)
			if(num > 1)
				do ans :+ 1
			end if
			do dic.add(a, num + 1)
		end for
	end for
	do cui@print("\{ans}\n")
end func