diff --git "a/\346\236\227\346\246\225\351\271\217/\347\254\254\344\270\200\346\254\241\344\275\234\344\270\232/count.js" "b/\346\236\227\346\246\225\351\271\217/\347\254\254\344\270\200\346\254\241\344\275\234\344\270\232/count.js"
new file mode 100644
index 0000000000000000000000000000000000000000..618cdc5f2898775d0a767a192ed07dccde790c6b
--- /dev/null
+++ "b/\346\236\227\346\246\225\351\271\217/\347\254\254\344\270\200\346\254\241\344\275\234\344\270\232/count.js"
@@ -0,0 +1,44 @@
+let count = {
+    add: function (num1, num2) {
+       
+        return (num1 + num2);
+    },
+    sub: function (num1, num2) {
+        
+        return (num1 - num2);
+    },
+    mul: function (num1, num2) {
+        
+        return num1 * num2;
+    },
+    div: function (num1, num2) {
+        
+        return num1 / num2;
+    },
+    count:function(num1,num2,symable){
+        if(!Number(num1)){
+            console.log("num1必须为数值");
+            throw new Error("num1必须为数值");
+        }
+        if(!Number(num2)){
+            console.log("num2必须为数值");
+            throw new Error("num2必须为数值");
+        }
+        // if(symable=="add"){
+        //     return this.add(num1,num2)
+        // }
+        // if(symable=="sub"){
+        //     return this.sub(num1,num2)
+        // }
+        // if(symable=="mul"){
+        //     return this.mul(num1,num2)
+        // }
+        // if(symable=="div"){
+        //     return this.div(num1,num2)
+        // }
+        return this[symable](Number(num1),Number(num2))
+    }
+}
+
+
+module.exports = count;
\ No newline at end of file
diff --git "a/\346\236\227\346\246\225\351\271\217/\347\254\254\344\270\200\346\254\241\344\275\234\344\270\232/homework.js" "b/\346\236\227\346\246\225\351\271\217/\347\254\254\344\270\200\346\254\241\344\275\234\344\270\232/homework.js"
new file mode 100644
index 0000000000000000000000000000000000000000..15b75a5c8297dc72e73c9b654789c8240ca157c9
--- /dev/null
+++ "b/\346\236\227\346\246\225\351\271\217/\347\254\254\344\270\200\346\254\241\344\275\234\344\270\232/homework.js"
@@ -0,0 +1,5 @@
+let count = require("./count.js");
+
+let result=count.count(20,10,"sub")
+
+console.log(result)
\ No newline at end of file