下列代码编译或运行的结果是:(     )

public class Foo {
    public String doit(int x, int y) { return "a";}
    public String doit(int[] vals) {return "b"; }
    public static void main(String[] args) {
        Foo f = new Foo();
        System.out.println(f.doit(4, 5)); 
    }
}