第三道Java小问题

public class Test {
		public static String f(short a, double b) {
			return "a is short";
		}

		public static String f(int a, float b) {
			return "a is int";
		}

		public static String f(double a, double b) {
			return "a is double";
		}

		public static String f(float a, float b) {
			return "a is float";
		}

		public static void main(String[] argu) {

			char a = 1;

			System.out.println(f(a, 4.5));

		}
	}

 

请问以上程序的输出是：