import math
def rectangle(x, y):
    return x*y
def triangle (x, y):
    return 0.5*x*y
def circle(x):
    return math.pi*pow(x,2)
print 
import math
def rectangle(x, y):
    return x*y
def triangle (x, y):
    return 0.5*x*y
def circle(x):
    return math.pi*pow(x,2)
print 