diff --git a/cmd/a.out b/cmd/a.out
deleted file mode 100755
index 4ce4616..0000000
Binary files a/cmd/a.out and /dev/null differ
diff --git a/cmd/main.go b/cmd/main.go
index 750e520..6bee94e 100644
--- a/cmd/main.go
+++ b/cmd/main.go
@@ -1,7 +1,11 @@
 package main
 
-import "fmt"
+import (
+	"fmt"
+	"gowinter/internal"
+)
 
 func main() {
 	fmt.Println("Welcome to rise field!!")
+	internal.Run()
 }
diff --git a/cmd/test.cpp b/cmd/test.cpp
deleted file mode 100644
index cc492a3..0000000
--- a/cmd/test.cpp
+++ /dev/null
@@ -1,19 +0,0 @@
-// C++ Code to demonstrate getppid() 
-#include <iostream> 
-#include <unistd.h> 
-using namespace std; 
-
-// Driver Code 
-int main() 
-{ 
-	int pid; 
-	pid = fork(); 
-	if (pid == 0) 
-	{ 
-		cout << "\nParent Process id : "
-			<< getpid() << endl; 
-		cout << "\nChild Process with parent id : "
-			<< getppid() << endl; 
-	} 
-	return 0; 
-} 
diff --git a/internal/example.go b/internal/example.go
new file mode 100644
index 0000000..6eebac6
--- /dev/null
+++ b/internal/example.go
@@ -0,0 +1,16 @@
+package internal
+
+import (
+	"fmt"
+	"time"
+)
+
+func Add(a, b int) {
+	time.Sleep(time.Second)
+	fmt.Println("Sum =", a+b)
+}
+
+func Sub(a, b int) {
+	time.Sleep(time.Second)
+	fmt.Println("Sub =", a-b)
+}
diff --git a/internal/simple_caluculator.go b/internal/simple_caluculator.go
new file mode 100644
index 0000000..7f46c96
--- /dev/null
+++ b/internal/simple_caluculator.go
@@ -0,0 +1,59 @@
+package internal
+
+import "fmt"
+
+var operators []string = []string{"+", "-", "*", "/"}
+
+func Run() {
+	var x, y int
+	var operator string
+
+	fmt.Println("Введите первое число")
+	_, err := fmt.Scan(&x)
+	if err != nil {
+		fmt.Printf("Некорректное число.\n")
+		return
+	}
+	fmt.Println("Введите операцию (+,-,*,/)")
+	fmt.Scan(&operator)
+	if !isExistOperato(operator) {
+		fmt.Printf("Некоректная операция.\n")
+		return
+	}
+	fmt.Println("Введите второе число")
+	_, err = fmt.Scan(&y)
+	if err != nil {
+		fmt.Printf("Некорректное число.\n")
+		return
+	}
+
+	calculate(x, y, operator)
+}
+
+func isExistOperato(operatop string) bool {
+	for _, op := range operators {
+		if op == operatop {
+			return true
+		}
+	}
+	return false
+}
+
+func calculate(x, y int, oprator string) {
+
+	switch oprator {
+	case "+":
+		fmt.Printf("%d + %d = %d\n", x, y, x+y)
+	case "-":
+		fmt.Printf("%d - %d = %d\n", x, y, x-y)
+	case "*":
+		fmt.Printf("%d * %d = %d\n", x, y, x*y)
+	case "/":
+		if y == 0 {
+			fmt.Println("Ошибка: деление на 0 невозможно")
+			return
+		}
+		fmt.Printf("%d + %d = %f\n", x, y, float64(x)/float64(y))
+	}
+
+}