diff --git a/cal4.java b/cal4.java
new file mode 100644
index 0000000..466b485
--- /dev/null
+++ b/cal4.java
@@ -0,0 +1,31 @@
+package xs1;
+
+import java.util.Scanner;
+
+public class cal4 {
+		public cal4() {
+			Scanner inScanner=new Scanner(System.in);
+			System.out.print("请输入第一位运算数：");
+			double a=inScanner.nextInt();
+			System.out.print("请输入第二位运算数：");
+			double b=inScanner.nextInt();
+			System.out.print("请输入将要运算的运算符：");
+			String op=inScanner.next();
+			char ch=op.charAt(0);
+			double sum=cala(a, b, ch);
+			System.out.println("结果为:"+sum);
+		}
+		
+		public static double cala(double x,double y,char op) {
+			switch (op) {
+			case '+': return x+y;
+			case '-': return x-y;
+			case '*': return x*y;
+			case '/': 
+				if(y==0) return 0;
+				else return x/y;
+			default:
+				return x;
+			}
+		}
+}