Bug with negative numbers

[Harshit-Gakhar]

When I add any number to a negative number, it returns additive inverse of first number and second number concatenated.

[agrawal-d]

@Harshit-Gakhar ,Thanks for pointing out the bug!
Actually, when you try to create a negative number, the app actually thinks you want to subtract the said number from zero ( if think about it, you'll get it) . I'll try to fix the bug soon.