fixes

src/Main.java

@@ -12,6 +12,16 @@ public class Main {
         String operation = scanner.next();
         float number2 = scanner.nextFloat();
         System.out.print("Ответ:");
+        String a = "+";
+        String b = "-";
+        String c = "*";
+        String d = ":";
+        String e = "^";
+
+
+        if (operation != a && operation != b && operation != c && operation != d && operation != e) {
+            System.out.println("ошибка");
+        }
 
         if (":".equals(operation)) {
             if (number2 != 0) {
@@ -36,5 +46,9 @@ public class Main {
             float multiplication = number1 * number2;
             System.out.println(multiplication);
         }
+        if ("^".equals(operation)) {
+            double power = Math.pow(number1, number2);
+            System.out.println(power);
+        }
     }
 }