QBASIC – Area of a circle

Below is the QBASIC program to calculate the area of a circle.

REM Program to find area of circle
CLS
INPUT "Enter the radius: "; r
area = 3.14 * r * r
PRINT "Area of the circle is: ";area
END

Explanation:

Let’s first see the formula: Area = pi * r * r, where the value of pi is 3.14. So, we can determine the area of a circle by taking the radius of the circle from the user and multiplying the value of pi with radius to the power of 2.