Simple Calculator

This problem requires you to implement a simple calculator that processes arithmetic operations. Each operation is provided in a single line in the format \(a \ operator \ b\), where a and b are integers and operator can be one of the following: +, -, *, or /. For division, compute the result using integer division, i.e. output \(\lfloor \frac{a}{b} \rfloor\) if b is not zero. If an operation is invalid or cannot be parsed correctly, output an appropriate error message. The program terminates processing when a line with exactly "end" is encountered.

inputFormat

The input is read from standard input (stdin). Each line contains a single arithmetic operation in the format "a operator b". The input ends when a line exactly matching "end" is encountered.

outputFormat

For each valid operation (except the terminating "end"), output the result or an error message on a separate line to standard output (stdout). The expected error messages are as follows:

• If the operator is not one of +, -, *, or /: output "Error: Invalid operator".
• If the inputs cannot be parsed as two integers followed by a valid operator: output "Error: Invalid input".
• If division by zero is attempted: output "Error: Division by zero".

3 + 4
10 - 5
6 * 7
8 / 2
10 / 0
end

7
5
42
4
Error: Division by zero