Calculator Requirements
UI
First launch
Application window (size, interface)
Buttons interface
Error messages
Languages
Default
Change languages
Errors languages
Error massages
Invalid input
Cannot divide by zero
System requirements
Operating System
CPU processor
Memory (RAM)
Application size (mb)
DirectX compatible
Possible input types
Allowed input
Maximum length
Decimal accuracy, rounding
Data input methods
Manipulator
Keyboard
Clipboard
Functionality
Keypad buttons
Operations
%
=
-
+
*
Negative (+/-)
Info
AC
Language
Hide
Close
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