diff --git a/src/small_computer/Main.java b/src/small_computer/Main.java
new file mode 100644
index 0000000..8388409
--- /dev/null
+++ b/src/small_computer/Main.java
@@ -0,0 +1,26 @@
+package small_computer;
+import java.util.Scanner;
+public class Main {
+
+	public static void main(String[] args) {
+		Subtraction ss=new Subtraction();
+		Division dd=new Division();
+		System.out.println("1-加法计算      2-减法运算");
+		System.out.println("3-乘法运算      4-除法计算");
+		System.out.println("请输入选择：");
+		Scanner sc=new Scanner(System.in);
+		int n=sc.nextInt();
+		System.out.println("请输入两个运算数：");
+		int a=sc.nextInt();
+		int b=sc.nextInt();
+		if(n==2) {
+			int c=(int) ss.sub(a, b);
+			System.out.println(c);
+		}
+		else if(n==4) {
+			int c=(int) dd.div(a, b);
+			System.out.println(c);
+		}
+	}
+
+}