# Write a program that gets a radius of a circle from a keyboard
# and displays the approximation of the circle's area.
# Use 3.14159 as the value for pi.



radius = int(input("Enter a radius of a circle : " ))
pi = 3.14159
area = pi * (radius ** 2)     # pi * radius * radius

print(area)
print("area = " + str(area))
print("area", area)

print("area of a circle with a radius of " + str(radius) + " is " + str(area))

area_formatted = format(area, ".2f")
print("formatted area = " + str(area_formatted))

area_formatted = "{:07.3f}".format(area)
print("another way to format : area_formatted = " + str(area_formatted))



# type casting
# str()
# float()
# int()