update

src/main.cpp

@@ -2,11 +2,51 @@
 #include "io.h"
 
 // Definition of function main()
+double get_user_double()
+{
+    std::cout << "Enter a double value: ";
+    double x{};
+    std::cin >> x;
+    return x;
+}
+char get_user_operator()
+{
+    std::cout << "Enter +, -, * or /: ";
+    char x{};
+    std::cin >> x;
+    return x;
+}
+void print_result(double a, double b, char c)
+{
+    double result{};
+    switch (c)
+    {
+    case '+':
+        result = a + b;
+        break;
+    case '-':
+        result = a - b;
+        break;
+    case '*':
+        result = a * b;
+        break;
+    case '/':
+        result = a / b;
+        break;
+    default:
+        return;
+    }
+    std::cout << a << ' ' << c << ' ' << b << " is " << result;
+}
+
 int main()
 {
     // add_two_numbers();
     // convert_char_to_ascii();
     // print_type_size_bytes();
-
+    double a{get_user_double()};
+    double b{get_user_double()};
+    char c{get_user_operator()};
+    print_result(a, b, c);
     return 0;
 }