Getting-standard output empty on ideone and WA here

I have done the Transform the expression question and its working perfectly fine in pc compiler
and showing correct output for every test case that I used.
But when I run that on Ideone its showing Success with Standard Output Empty.

And here too its showing wrong answer. I don’t know whats the problem with this.

show the code

Whenever you are asking questions related to your submitted solution please provide the link to the solution.

Regarding your WA:
You are using strlen() method to determine the length of out[] but no where in the out you are storing ‘\0’ to end the string. strlen() counts the string length till it finds ‘\0’(null character) in the string.
That is the reason you are getting WA.
Here is the link to the corrected version of your solution :