Perimeter of circle is 2*3.14*r
program -
r=input("Enter radius of circlen")
r=int(r)
perimeter=2*3.14*r
print("Area of circle is "+str(perimeter))
output -
Enter radius of circle
3
Area of circle is 18.84
In this program, we take radius as a input from the user side then we change the radius to integer beacuse by default input return str data type. then we calculate the perimeter and store in variable 'perimeter' and then we print that variable.