Calculator

Use the "buttons" or "click" on the keyboard to input numbers and operators.
Use "Clr" button or Click "Ctrl + Backspace" to clear the input field.
Use "Del" button or Click "Backspace" to delete the last character.
To calculate Factorial, enter the number(less than 1 lakh) followed by "!" button or Click "f" on the keyboard.
To calculate Remainder, Use "mod" button.
To check Prime number, Use "Prime" button.
Click "h" or Use "History" button to see past calculated results.