Hi everyone this is my Calculator project 
Every critique is welcome!
I think i messed up something 
I did 88 * X/2 CE 0 0 + 7
You will see a NaN after the third command, which you will edit with CE ( becoming Na) and then add 00+7 resulting in Na00+7
I’d suggest you to block the potential ‘NaN’: i think the X/2 will divide the actual value, but if the value is not a number (i.e. 35+ or anything else) it will fail.
Besides that i tried to play around but i didn’t find anything wrong 
Thanks for the a feedback…I Will try to fix this error later today.