def area(p,q):return p[0]*q[1]-p[1]*q[0]

 

n=int(eval(input()))

point=[]

x_1,y_1=[int(i) for i in input().split(" ")]

 

for _ in range(n-1):

    x,y=[int(i) for i in input().split(" ")]

    point.append([x-x_1,y-y_1])

a=0

for i in range(n-2):a+=area(point[i],point[i+1])

print((a*0.5))
n=int(eval(input()))

point=[]

x_1,y_1=[int(i) for i in input().split(" ")]

 

for _ in range(n-1):

    x,y=[int(i) for i in input().split(" ")]

    point.append([x-x_1,y-y_1])

a=0

for i in range(n-2):a+=point[i][0]*point[i+1][1] - point[i][1]*point[i+1][0]

print((a*0.5))
def area(p, q):
    return p[0] * q[1] - p[1] * q[0]


n = int(eval(input()))
point = []
x_1, y_1 = [int(i) for i in input().split(" ")]
for _ in range(n - 1):
    x, y = [int(i) for i in input().split(" ")]
    point.append([x - x_1, y - y_1])
a = 0
for i in range(n - 2):
    a += area(point[i], point[i + 1])
print((a * 0.5))

n = int(eval(input()))
point = []
x_1, y_1 = [int(i) for i in input().split(" ")]
for _ in range(n - 1):
    x, y = [int(i) for i in input().split(" ")]
    point.append([x - x_1, y - y_1])
a = 0
for i in range(n - 2):
    a += point[i][0] * point[i + 1][1] - point[i][1] * point[i + 1][0]
print((a * 0.5))

-def area(p, q): -    return p[0] * q[1] - p[1] * q[0] - - -    a += area(point[i], point[i + 1]) +    a += point[i][0] * point[i + 1][1] - point[i][1] * point[i + 1][0]