def cross(a,b):return a[0]*b[1] - a[1]*b[0]

        

n = int(eval(input()))

P =[]

s = 0

for i in range(n):P.append([int(i) for i in input().split()])

P = P*2

for i in range(n):s += cross(P[i],P[i+1])

print((abs(s)/2))
def cross(a,b):return a[0]*b[1] - a[1]*b[0]

        

n = int(eval(input()))

P =[]

s = 0

for i in range(n):P.append([int(i) for i in input().split()])

P.append(P[0])

for i in range(n):s += cross(P[i],P[i+1])

print((abs(s)*0.5))
def cross(a, b):
    return a[0] * b[1] - a[1] * b[0]


n = int(eval(input()))
P = []
s = 0
for i in range(n):
    P.append([int(i) for i in input().split()])
P = P * 2
for i in range(n):
    s += cross(P[i], P[i + 1])
print((abs(s) / 2))

def cross(a, b):
    return a[0] * b[1] - a[1] * b[0]


n = int(eval(input()))
P = []
s = 0
for i in range(n):
    P.append([int(i) for i in input().split()])
P.append(P[0])
for i in range(n):
    s += cross(P[i], P[i + 1])
print((abs(s) * 0.5))

-P = P * 2 +P.append(P[0]) -print((abs(s) / 2)) +print((abs(s) * 0.5))