料理需要多少种不同的材料
下厨房
http://www.nowcoder.com/questionTerminal/ca5c9ba9ebac4fd5ae9ba46114b0f476
用集合做：
import java.util.*;
public class Main {
public static void main(String[] args) throws Exception{
Scanner sc = new Scanner(System.in);
Set<String> s = new HashSet<>();
while(sc.hasNext()) s.add(sc.next());
System.out.println(s.size());
}
}