public/subjects/doop.en.md

## doop

### Instructions

Write a program that is called `doop`.

The program has to be used with three arguments:

- A value
- An operator
- Another value

You should use `int64`.

The following operators are considered valid: `+`, `-`, `/`, `*`, `%`.

In case of an invalid operator or overflow the programs prints `0`.

In case of an invalid number of arguments the program prints nothing.

The program has to handle the modulo and division operations by 0 as shown on the output examples below.

### Usage

```console
student@ubuntu:~/[[ROOT]]/test$ go build doop.go
student@ubuntu:~/[[ROOT]]/test$ ./doop
student@ubuntu:~/[[ROOT]]/test$ ./doop 1 + 1 | cat -e
2$
student@ubuntu:~/[[ROOT]]/test$ ./doop hello + 1 | cat -e
0$
student@ubuntu:~/[[ROOT]]/test$ ./doop 1 p 1 | cat -e
0$
student@ubuntu:~/[[ROOT]]/test$ ./doop 1 / 0 | cat -e
No division by 0$
student@ubuntu:~/[[ROOT]]/test$ ./doop 1 % 0 | cat -e
No modulo by 0$
student@ubuntu:~/[[ROOT]]/test$ ./doop 9223372036854775807 + 1
0
student@ubuntu:~/[[ROOT]]/test$ ./doop -9223372036854775809 - 3
0
student@ubuntu:~/[[ROOT]]/test$ ./doop 9223372036854775807 "*" 3
0
student@ubuntu:~/[[ROOT]]/test$ ./doop 1 "*" 1
1
student@ubuntu:~/[[ROOT]]/test$ ./doop 1 "*" -1
-1
student@ubuntu:~/[[ROOT]]/test$
```