def trapezium_area(w1, w2, h):
    return h * (w1 + w2) / 2

w1 = int(input("Width of the top:    "))
w2 = int(input("Width of the bottom: "))
h = int(input("Height:              "))
print(f"Area is {trapezium_area(w1, w2, h)}")