changing overflow cases

subjects/doop.en.md

@@ -14,13 +14,11 @@ You should use `int64`.
 
 The following operators are considered valid: `+`, `-`, `/`, `*`, `%`.
 
-In case of an invalid operator the programs prints `0`.
+In case of an invalid operator or overflow the programs prints `0`.
 
 In case of an invalid number of arguments the program prints nothing.
 
-In case the result gives overflow the program prints `Overflow`.
-
-The program has to handle the module and division operations by 0 as shown on the output examples below.
+The program has to handle the modulo and division operations by 0 as shown on the output examples below.
 
 ### Usage
 
@@ -38,11 +36,11 @@ No division by 0$
 student@ubuntu:~/piscine-go/test$ ./doop 1 % 0 | cat -e
 No Modulo by 0$
 student@ubuntu:~/piscine-go/test$ ./doop 9223372036854775807 + 1
-Overflow
+0
 student@ubuntu:~/piscine-go/test$ ./doop -9223372036854775809 "*" 3
 0
 student@ubuntu:~/piscine-go/test$ ./doop 9223372036854775807 "*" 3
-Overflow
+0
 student@ubuntu:~/piscine-go/test$ ./doop 1 "*" 1
 1
 student@ubuntu:~/piscine-go/test$ ./doop 1 "*" -1