The app was made with Angular CLI version 13.0.1, and Spring Boot version 2.5.7 with JAVA Spring Boot.

This is Calculator web application by angular framework and spring boot. It allows to make several operations but give you the result every time you enter for new operand

• For Front-end, it is on port 4200
• For Back-end, it is on port 8080

The calculator supports basic operations. I classified them into two operands operations:

• Addition
• Subtraction
• Multiplication
• Division

And one operand operations:

• Change the sign
• Invert
• Percentage
• Square root
• Squaring

1. For using the web app, you can use your first operand then second operand then the operation.

2. If you selected new operation the result of last calculation is stored and will be calculated in the new operation as first operand and the user enter the second operand.

3. The last operand-or the result of last operation- and current operation will be visible in the app.

4. If the equal button is pressed the user has the option to use the result in new operation or start a new calculation.

5. Use CE to erases the current operand that you are inputting and C for clear all history.

6. Use DEL button erases the last digit of operand.

7. There is no division by ZERO allowed and no square root for NEGATIVE numbers.

8. The user is not allowed to enter more than 9 digits in the screen

9. The user can change the operation before entering the input for the new operand

To get more help on the Angular CLI use ng help or go check out the Angular CLI Overview and Command Reference page.