함수 실습

def a_rectangleArea():
    print(5*7)

def b_rectagleArea(x, y):
    print(x * y)

def c_rectagleArea():
    return (5*7)

def d_rectagleArea(x, y):
    return ( x*y )

a_rectangleArea()
b_rectagleArea(5,7)
print(c_rectagleArea())
print(d_rectagleArea(5,7))

* a_rectagleArea와 b_rectagleArea는 return값이 없으므로 print함수에 넣으면 null을 출력한다.