How to input root in a program

Question

In the input box which appears for cin

Answer 1

THANKS

Answer 2

What exactly do mean with input root?

Answer 3

I mean to enter square root of a number

Answer 4

Actually I mad a quadratic equations program and when I input coefficients i want enter values like sqrt 2

Answer 5

In the input box

Answer 6

2 squared is usually written as 2^2 so you could write 2^0.5 for sqrt 2. You could use the sqrt sign √, too but I doubt that every keyboard has this letter.
Since it's text input you can decide how to handle it. You could even allow the user to simply type sqrt(2).