Problem Description

A simple calculator that supports four operations: +, -, *, /. Only integer inputs and outputs are considered, and the data and operation results will not exceed the range representable by int. However:

1. If the divisor is zero, the output should be: Divided by zero!.

2. If an invalid operator (not one of +, -, *, /) is encountered, the output should be: Invalid operator!.

3. The division operator represents integer division, with the result rounded towards zero.

Input Format

The input consists of a single line with three parameters, where the first two parameters are integers and the third parameter is an operator (+, -, *, /).

Output Format

The output consists of a single line, which is an integer representing the operation result. However:

1. If the divisor is zero, the output should be: Divided by zero!.

2. If an invalid operator (not one of +, -, *, /) is encountered, the output should be: Invalid operator!.

Sample Input and Output

Sample Input #1

1 2 +

Sample Output #1

3

Sample Input #2

2 4 *

Sample Output #2

8

Sample Input #3

5 0 /

Sample Output #3

Divided by zero!

见题面 Input 部分

见题面 Output 部分